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Michael De Volder, Engineering Department - IfM

Studying at Cambridge

Nanoscience News

The Fluorination of C−H Bonds: Developments and Perspectives

By Robert Szpera, Daniel F. J. Moseley, Lewis B. Smith, Alistair J. Sterling, Véronique Gouverneur from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 20, 2019.

The direct fluorination of C−H bonds has emerged as a powerful method for accessing functional molecules such as pharmaceuticals or PET radiotracers. This Review provides an overview of the state of play of this field with an emphasis on the advantages and limitations of the main activation modes exploited to date. The discussion brings to light the importance of the fluorination reagent, and the challenges associated with nucleophilic C−H fluorination methods. Abstract This Review summarizes advances in fluorination by C(sp2)−H and C(sp3)−H activation. Transition‐metal‐catalyzed approaches championed by palladium have allowed the installation of a fluorine substituent at C(sp2) and C(sp3) sites, exploiting the reactivity of high‐oxidation‐state transition‐metal fluoride complexes combined with the use of directing groups (some transient) to control site and stereoselectivity. The large majority of known methods employ electrophilic fluorination reagents, but methods combining a nucleophilic fluoride source with an oxidant have appeared. External ligands have proven to be effective for C(sp3)−H fluorination directed by weakly coordinating auxiliaries, thereby enabling control over reactivity. Methods relying on the formation of radical intermediates are complementary to transition‐metal‐catalyzed processes as they allow for undirected C(sp3)−H fluorination. To date, radical C−H fluorinations mainly employ electrophilic N−F fluorination reagents but a unique MnIII‐catalyzed oxidative C−H fluorination using fluoride has been developed. Overall, the field of late‐stage nucleophilic C−H fluorination has progressed much more slowly, a state of play explaining why C−H 18F‐fluorination is still in its infancy.

Fri 23 Aug 11:00: Two Approximate Sampling Methods for Bayesian Deep Learning

From All Talks (aka the CURE list). Published on Aug 20, 2019.

Two Approximate Sampling Methods for Bayesian Deep Learning

Deep neural networks have become popular for many tasks, especially object classification, in computer vision and machine learning. However, these classes of models are known to be have poor uncertainty representations – e.g. they do not know what they do not know. To address this challenge, we propose two Bayesian approaches to approximate the posterior distribution of the models’ parameters. The first, termed stochastic weight averaging Gaussian (SWAG), fits a Gaussian approximation around the iterates of the stochastic gradient descent trajectory from standard training of DNNs. The second, subspace inference, instead reduces the high dimensionality of DNNs to very low dimensions, before performing Bayesian model averaging in that low dimensional subspace. Both methods draw on existing theory and are demonstrated to have strong empirical results on both regression and classification, scaling to even ImageNet-sized datasets.

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Wed 28 Aug 11:15: A Square-Lattice Spin Liquid Candidate

From All Talks (aka the CURE list). Published on Aug 20, 2019.

A Square-Lattice Spin Liquid Candidate

Abstract not available

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Thu 28 Nov 16:00: Title to be confirmed

From All Talks (aka the CURE list). Published on Aug 20, 2019.

Title to be confirmed

Abstract not available

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Thu 10 Oct 16:00: Title to be confirmed

From All Talks (aka the CURE list). Published on Aug 20, 2019.

Title to be confirmed

Abstract not available

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[ASAP] Ultrastrong and Stiff Carbon Nanotube/Aluminum–Copper Nanocomposite via Enhancing Friction between Carbon Nanotubes

By G. J. Wang, Y. P. Cai, Y. J. Ma, S. C. Tang, J. A. Syed, Z. H. Cao*, and X. K. Meng* from Nano Letters: Latest Articles (ACS Publications). Published on Aug 20, 2019.

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Nano Letters
DOI: 10.1021/acs.nanolett.9b02332

[ASAP] Disorder-to-Order Transition Mediated by Size Refocusing: A Route toward Monodisperse Intermetallic Nanoparticles

By Hannah M. Ashberry†, Jocelyn T. L. Gamler†, Raymond R. Unocic‡, and Sara E. Skrabalak*† from Nano Letters: Latest Articles (ACS Publications). Published on Aug 20, 2019.

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Nano Letters
DOI: 10.1021/acs.nanolett.9b02610

[ASAP] Atomically Thin Nonlinear Transition Metal Dichalcogenide Holograms

By Arindam Dasgupta, Jie Gao*, and Xiaodong Yang* from Nano Letters: Latest Articles (ACS Publications). Published on Aug 20, 2019.

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Nano Letters
DOI: 10.1021/acs.nanolett.9b02740

[ASAP] Enhancing Photoluminescence and Mobilities in WS2 Monolayers with Oleic Acid Ligands

By Arelo O. A Tanoh†‡, Jack Alexander-Webber§, James Xiao†, Ge´raud Delport†, Cyan A. Williams‡?, Hope Bretscher†, Nicolas Gauriot†, Jesse Allardice†, Raj Pandya†, Ye Fan§, Zhaojun Li†, Silvia Vignolini?, Samuel D. Stranks†, Stephan Hofmann§, and Akshay Rao†* from Nano Letters: Latest Articles (ACS Publications). Published on Aug 20, 2019.

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Nano Letters
DOI: 10.1021/acs.nanolett.9b02431

[ASAP] Simultaneous Identification of Low and High Atomic Number Atoms in Monolayer 2D Materials Using 4D Scanning Transmission Electron Microscopy

By Yi Wen†, Colin Ophus‡, Christopher S. Allen†§, Shiang Fang?, Jun Chen†, Efthimios Kaxiras?¶, Angus I. Kirkland†§, and Jamie H. Warner*† from Nano Letters: Latest Articles (ACS Publications). Published on Aug 20, 2019.

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Nano Letters
DOI: 10.1021/acs.nanolett.9b02717

[ASAP] Motility of Enzyme-Powered Vesicles

By Subhadip Ghosh†, Farzad Mohajerani‡, Seoyoung Son#, Darrell Velegol‡, Peter J. Butler#, and Ayusman Sen*† from Nano Letters: Latest Articles (ACS Publications). Published on Aug 20, 2019.

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Nano Letters
DOI: 10.1021/acs.nanolett.9b01830

[ASAP] Engineering and Modeling the Electrophoretic Trapping of a Single Protein Inside a Nanopore

By Kherim Willems†‡?, Dino Ruic´‡§?, Annemie Biesemans†?, Nicole Ste´phanie Galenkamp?, Pol Van Dorpe‡§, and Giovanni Maglia*? from ACS Nano: Latest Articles (ACS Publications). Published on Aug 20, 2019.

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ACS Nano
DOI: 10.1021/acsnano.8b09137

[ASAP] Stable and Colorful Perovskite Solar Cells Using a Nonperiodic SiO2/TiO2 Multi-Nanolayer Filter

By Gang Yeol Yoo†?, Randi Azmi‡§?, Changwook Kim‡, Woong Kim†, Byoung Koun Min?#, Sung-Yeon Jang*§, and Young Rag Do*‡ from ACS Nano: Latest Articles (ACS Publications). Published on Aug 20, 2019.

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ACS Nano
DOI: 10.1021/acsnano.9b03098

[ASAP] Correction to “Pt-like Hydrogen Evolution Electrocatalysis on PANI/CoP Hybrid Nanowires by Weakening the Shackles of Hydrogen Ions on the Surfaces of Catalysts”

By Jin-Xian Feng, Si-Yao Tong, Ye-Xiang Tong, and Gao-Ren Li* from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 20, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b06907

[ASAP] Resorcinarene Cavitand Polymers for the Remediation of Halomethanes and 1,4-Dioxane

By Luke P. Skala, Anna Yang, Max J. Klemes, Leilei Xiao, and William R. Dichtel* from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 20, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b06749

[ASAP] Correction to “Efficient Hydrogen Evolution on Cu Nanodots-Decorated Ni3S2 Nanotubes by Optimizing Atomic Hydrogen Adsorption and Desorption”

By Jin-Xian Feng, Jin-Qi Wu, Ye-Xiang Tong, and Gao-Ren Li* from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 20, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b06861

[ASAP] Impact of Aromatic Stacking on Glycoside Reactivity: Balancing CH/p and Cation/p Interactions for the Stabilization of Glycosyl-Oxocarbenium Ions

By Laura Montalvillo-Jime´nez?†, Andre´s G. Santana?†, Francisco Corzana‡, Gonzalo Jime´nez-Ose´s§, Jesu´s Jime´nez-Barbero§?, Ana M. Go´mez†, and Juan Luis Asensio*† from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 20, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b03285

[ASAP] Divergent Catalytic Strategies for the Cis/Trans Stereoselective Ring-Opening Polymerization of a Dual Cyclic Carbonate/Olefin Monomer

By Thomas M. McGuire†, Ce´cile Pe´rale†, Re´mi Castaing‡, Gabriele Kociok-Ko¨hn‡, and Antoine Buchard*† from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 20, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b06259

[ASAP] Multivariate Metal–Organic Frameworks for the Simultaneous Capture of Organic and Inorganic Contaminants from Water

By Marta Mon†#, Rosaria Bruno§#, Estefania Tiburcio†, Marta Viciano-Chumillas†, Lucas H. G. Kalinke†‡, Jesu´s Ferrando-Soria*†, Donatella Armentano*§, and Emilio Pardo*† from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 20, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b06250

Al2O3 coating layer on mesoporous Si nanosphere for stable solid electrolyte interphase and high-rate capacity for lithium ion batteries

By Yitai Qian from RSC - Nanoscale latest articles. Published on Aug 20, 2019.

Nanoscale, 2019, Accepted Manuscript
DOI: 10.1039/C9NR05264J, Paper
Na Li, Zheng Yi, Ning Lin, Yitai Qian
The application of Si-based anode materials is hindered by the huge volume change, poor cycling stability, and low coulombic efficiency. Solving these problems generally need the combination of various strategies,...
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Synergy of sp-N and sp2-N Codoping Endows Graphdiyne with Comparable Oxygen Reduction Reaction Performance to Pt

By Jin Yong Lee from RSC - Nanoscale latest articles. Published on Aug 20, 2019.

Nanoscale, 2019, Accepted Manuscript
DOI: 10.1039/C9NR05363H, Paper
Baotao Kang, Si Wu, Jiapeng Ma, Hongqi Ai, Jin Yong Lee
Nitrogen doped graphdiyne (NGDY) has been reported to have comparable oxygen reduction reaction (ORR) performance to Pt-based catalysts. However, the source of this enhanced ORR performance is not clearly understood....
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Integration of Multi-scale Defects for Optimizing Thermoelectric Properties of N-Type Cu1-xCdxFeS2 (x=0-0.1)

By Guanjun Qiao from RSC - Nanoscale latest articles. Published on Aug 20, 2019.

Nanoscale, 2019, Accepted Manuscript
DOI: 10.1039/C9NR04693C, Paper
Bangzhi Ge, Jiabin Hu, Zhongqi Shi, Hailong Wang, Hongyan Xia, Guanjun Qiao
The performance of thermoelectric (TE) materials is strongly influenced by the multi-scale defects. Some defects can improve the TE performance but some are unfavorable. Therefore, the multi-scale defects need to...
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Carbon Dots: advances in nanocarbons applications

By Shuit-Tong Lee from RSC - Nanoscale latest articles. Published on Aug 20, 2019.

Nanoscale, 2019, Accepted Manuscript
DOI: 10.1039/C9NR05647E, Minireview
Zhenhui Kang, Shuit-Tong Lee
Carbon dots (C-Dots), defined by characteristic sizes of ˂10 nm, have become a rising star in carbon nanomaterials. C-Dots exhibit many unique physiochemical and photochemical properties making them a promising...
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In Situ Growth of Ultrasmall Cesium Lead Bromine Quantum Dots into Mesoporous Silica Matrix and Its Application in Flexible Light-Emitting Diode

By Ning Dai from RSC - Nanoscale latest articles. Published on Aug 20, 2019.

Nanoscale, 2019, Accepted Manuscript
DOI: 10.1039/C9NR05731E, Paper
Peng Chen, Yufeng Liu, Zhijun Zhang, Yan Sun, Jingshan Hou, Guoying Zhao, Jun Zou, Yongzheng Fang, Jiayue Xu, Ning Dai
Recently, CsPbX3 (X = Cl, Br, and I) perovskite quantum dots (QDs) exhibit great potential in the fields of lighting. The self-absorption and agglomeration are remarkable to decline its photoluminescence...
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Direct Synthesis of Core-shell MFI Zeolite with Spatially Tapered Trimodal Mesopores via Controlled Orthogonal Self-Assembly

By Mei Hong from RSC - Nanoscale latest articles. Published on Aug 20, 2019.

Nanoscale, 2019, Accepted Manuscript
DOI: 10.1039/C9NR01497G, Paper
Zhuwen Chen, Lei Dong, Chao Chen, Yanding Wang, Ya Wang, Jian Zhang, Wei Qian, Mei Hong
Manipulating pore hierarchy in porous materials is an attractive, yet difficult challenge in crystalline zeolites. Here we report core-shell MFI zeolite having trimodal mesopores with size gradually decreasing from surface...
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Volumetric Bioprinting of Complex Living‐Tissue Constructs within Seconds

By Paulina Nuñez Bernal, Paul Delrot, Damien Loterie, Yang Li, Jos Malda, Christophe Moser, Riccardo Levato from Wiley: Advanced Materials: Table of Contents. Published on Aug 19, 2019.

Spatially coordinated patterns of visible light tomographic projections onto cell‐laden photoresponsive hydrogels enable the rapid bioprinting of 3D tissue constructs with clinically relevant size and complex geometries. Centimeter‐scale structures are built within seconds, outperforming conventional layer‐by‐layer bioprinting approaches and demonstrating high cell viability. Stem cells retain functionality postprinting, demonstrating potential for the biofabrication of vascularized and mature tissue grafts. Abstract Biofabrication technologies, including stereolithography and extrusion‐based printing, are revolutionizing the creation of complex engineered tissues. The current paradigm in bioprinting relies on the additive layer‐by‐layer deposition and assembly of repetitive building blocks, typically cell‐laden hydrogel fibers or voxels, single cells, or cellular aggregates. The scalability of these additive manufacturing technologies is limited by their printing velocity, as lengthy biofabrication processes impair cell functionality. Overcoming such limitations, the volumetric bioprinting of clinically relevant sized, anatomically shaped constructs, in a time frame ranging from seconds to tens of seconds is described. An optical‐tomography‐inspired printing approach, based on visible light projection, is developed to generate cell‐laden tissue constructs with high viability (>85%) from gelatin‐based photoresponsive hydrogels. Free‐form architectures, difficult to reproduce with conventional printing, are obtained, including anatomically correct trabecular bone models with embedded angiogenic sprouts and meniscal grafts. The latter undergoes maturation in vitro as the bioprinted chondroprogenitor cells synthesize neo‐fibrocartilage matrix. Moreover, free‐floating structures are generated, as demonstrated by printing functional hydrogel‐based ball‐and‐cage fluidic valves. Volumetric bioprinting permits the creation of geometrically complex, centimeter‐scale constructs at an unprecedented printing velocity, opening new avenues for upscaling the production of hydrogel‐based constructs and for their application in tissue engineering, regenerative medicine, and soft robotics.

Bioinspired Core–Shell Nanoparticles for Hydrophobic Drug Delivery

By Guangze Yang, Yun Liu, Haofei Wang, Russell Wilson, Yue Hui, Lei Yu, David Wibowo, Cheng Zhang, Andrew K. Whittaker, Anton P. J. Middelberg, Chun‐Xia Zhao from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

Difunctional amphiphilic peptides were designed to not only stabilize hydrophobic drug nanoparticles but also induce biosilicification at the drug particle surface to maintain the long‐term stability of the nano‐drug. The drug‐core silica–shell nanocomposites have exceptionally high drug loading (up to 65 % w/w) and encapsulation efficiencies (>99 %). Abstract A large range of nanoparticles have been developed to encapsulate hydrophobic drugs. However, drug loading is usually less than 10 % or even 1 %. Now, core–shell nanoparticles are fabricated having exceptionally high drug loading up to 65 % (drug weight/the total weight of drug‐loaded nanoparticles) and high encapsulation efficiencies (>99 %) based on modular biomolecule templating. Bifunctional amphiphilic peptides are designed to not only stabilize hydrophobic drug nanoparticles but also induce biosilicification at the nanodrug particle surface thus forming drug‐core silica–shell nanocomposites. This platform technology is highly versatile for encapsulating various hydrophobic cargos. Furthermore, the high drug loading nanoparticles lead to better in vitro cytotoxic effects and in vivo suppression of tumor growth, highlighting the significance of using high drug‐loading nanoparticles.

Hemilabile Ligands as Mechanosensitive Electrode Contacts for Molecular Electronics

By Nicolò Ferri, Norah Algethami, Andrea Vezzoli, Sara Sangtarash, Maeve McLaughlin, Hatef Sadeghi, Colin J. Lambert, Richard J. Nichols, Simon J. Higgins from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

Contact request: Molecular junctions with hemilabile contact moieties show enhanced mechanoresistive behaviour. The molecule–metal contact is forced to transition from a monodentate to a bidentate configuration as the junction is compressed and stretched, with a resulting modulation in conductance of up to two orders of magnitude. Abstract Single‐molecule junctions that are sensitive to compression or elongation are an emerging class of nanoelectromechanical systems (NEMS). Although the molecule–electrode interface can be engineered to impart such functionality, most studies to date rely on poorly defined interactions. We focused on this issue by synthesizing molecular wires designed to have chemically defined hemilabile contacts based on (methylthio)thiophene moieties. We measured their conductance as a function of junction size and observed conductance changes of up to two orders of magnitude as junctions were compressed and stretched. Localised interactions between weakly coordinating thienyl sulfurs and the electrodes are responsible for the observed effect and allow reversible monodentate⇄bidentate contact transitions as the junction is modulated in size. We observed an up to ≈100‐fold sensitivity boost of the (methylthio)thiophene‐terminated molecular wire compared with its non‐hemilabile (methylthio)benzene counterpart and demonstrate a previously unexplored application of hemilabile ligands to molecular electronics.

Local Structure and Coordination Define Adsorption in a Model Ir1/Fe3O4 Single‐Atom Catalyst

By Zdenek Jakub, Jan Hulva, Matthias Meier, Roland Bliem, Florian Kraushofer, Martin Setvin, Michael Schmid, Ulrike Diebold, Cesare Franchini, Gareth S. Parkinson from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

The coordination of a single atom to the oxide support has dramatic consequences on its ability to adsorb carbon monoxide. The observed motifs can be rationalized using simple arguments from coordination chemistry, confirming the hypothesis that single‐atom catalysts have much in common with organometallic complexes used in homogeneous catalysis. Abstract Single‐atom catalysts (SACs) bridge homo‐ and heterogeneous catalysis because the active site is a metal atom coordinated to surface ligands. The local binding environment of the atom should thus strongly influence how reactants adsorb. Now, atomically resolved scanning‐probe microscopy, X‐ray photoelectron spectroscopy, temperature‐programmed desorption, and DFT are used to study how CO binds at different Ir1 sites on a precisely defined Fe3O4(001) support. The two‐ and five‐fold‐coordinated Ir adatoms bind CO more strongly than metallic Ir, and adopt structures consistent with square‐planar IrI and octahedral IrIII complexes, respectively. Ir incorporates into the subsurface already at 450 K, becoming inactive for adsorption. Above 900 K, the Ir adatoms agglomerate to form nanoparticles encapsulated by iron oxide. These results demonstrate the link between SAC systems and coordination complexes, and that incorporation into the support is an important deactivation mechanism.

Understanding Hydrogen Bonding Interactions in Crosslinked Methylammonium Lead Iodide Crystals: Towards Reducing Moisture and Light Degradation Pathways

By Wendy J. Nimens, Sarah J. Lefave, Laura Flannery, Jonathan Ogle, Detlef‐M. Smilgies, Matthew T. Kieber‐Emmons, Luisa Whittaker‐Brooks from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

Crosslinked perovskite crystals: Incorporation of π‐conjugated organic crosslinkers into the organic‐inorganic hybrid perovskite structure imparts stability towards light and high moisture degradation without compromising power conversion efficiencies. Abstract Methylammonium lead halide perovskite‐based solar cells have demonstrated efficiencies as high as 24.2 %, highlighting their potential as inexpensive and solution‐processable alternatives to silicon solar cell technologies. Poor stability towards moisture, ultraviolet irradiation, heat, and a bias voltage of the perovskite layer and its various device interfaces limits the commercial feasibility of this material for outdoor applications. Herein, we investigate the role of hydrogen bonding interactions induced when metal halide perovskite crystals are crosslinked with alkyl or π‐conjugated boronic acid small molecules (‐B(OH)2). The crosslinked perovskite crystals are investigated under continuous light irradiation and moisture exposure. These studies demonstrate that the origin of the interaction between the alkyl or π‐conjugated crosslinking molecules is due to hydrogen bonding between the ‐B(OH)2 terminal group of the crosslinker and the I of the [PbI6]4− octahedra of the perovskite layer. Also, this interaction influences the stability of the perovskite layer towards moisture and ultraviolet light irradiation. Morphology and structural analyses, as well as IR studies as a function of aging under both dark and light conditions show that π‐conjugated boronic acid molecules are more effective crosslinkers of the perovskite crystals than their alkyl counterparts thus imparting better stability towards light and moisture degradation.

Bridging Crystal Engineering and Drug Discovery by Utilizing Intermolecular Interactions and Molecular Shapes in Crystals

By Peter R. Spackman, Li‐Juan Yu, Craig J. Morton, Michael W. Parker, Charles S. Bond, Mark A. Spackman, Dylan Jayatilaka, Sajesh P. Thomas from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

Crystal clear: Highly efficient profiling of intermolecular interactions and molecular shape in crystal structures led to a new drug‐discovery approach that combines small‐molecule crystallography and protein crystallography to identify potential ligand molecules from the Cambridge Structural Database. Abstract Most structure‐based drug discovery methods utilize crystal structures of receptor proteins. Crystal engineering, on the other hand, utilizes the wealth of chemical information inherent in small‐molecule crystal structures in the Cambridge Structural Database (CSD). We show that the interaction surfaces and shapes of molecules in experimentally determined small‐molecule crystal structures can serve as effective tools in drug discovery. Our description of the shape and interaction propensities of molecules in their crystal structures can be used to screen them for specific binding compatibility with protein targets, as demonstrated through the high‐throughput profiling of around 138 000 small‐molecule structures in the CSD and a series of drug–protein crystal structures. Electron‐density‐based intermolecular boundary surfaces in small‐molecule crystal structures and in target‐protein pockets are utilized to identify potential ligand molecules from the CSD based on 3D shape and intermolecular interaction matching.

Realization of Lewis Basic Sodium Anion in the NaBH3− Cluster

By Gaoxiang Liu, Nikita Fedik, Chalynette Martinez‐Martinez, Sandra M. Ciborowski, Xinxing Zhang, Alexander I. Boldyrev, Kit H. Bowen from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

Alkalide as Lewis base: The Lewis acid/base adduct NaBH3− has been made and characterized by anion photoelectron spectroscopy. Na− acts as the Lewis base that forms a directional dative chemical bond with BH3. Abstract We report a Na:−→B dative bond in the NaBH3− cluster, which was designed on the principle of minimum‐energy rupture, prepared by laser vaporization, and characterized by a synergy of anion photoelectron spectroscopy and electronic structure calculations. The global minimum of NaBH3− features a Na−B bond. Its preferred heterolytic dissociation conforms with the IUPAC definition of dative bond. The lone electron pair revealed on Na and the negative Laplacian of electron density at the bond critical point further confirm the dative nature of the Na−B bond. This study represents the first example of a Lewis adduct with an alkalide as the Lewis base.

2D Poly(arylene vinylene) Covalent Organic Frameworks via Aldol Condensation of Trimethyltriazine

By Thaksen Jadhav, Yuan Fang, William Patterson, Cheng‐Hao Liu, Ehsan Hamzehpoor, Dmitrii F. Perepichka from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

Crystalline 2D poly(arylene vinylene) covalent organic frameworks (COFs) have been synthesized by base‐catalyzed aldol condensation of trimethyltriazine with a series of aromatic dialdehydes. The resulting COFs are hydrolytically stable and highly fluorescent (quantum yield ≤50 %). Addition of protic solvents results in a dramatic and reversible expansion of the bulk volume and red shifted emission of the COF. Abstract Designing structural order in electronically active organic solids remains a great challenge in the field of materials chemistry. Now, 2D poly(arylene vinylene)s prepared as highly crystalline covalent organic frameworks (COFs) by base‐catalyzed aldol condensation of trimethyltriazine with aromatic dialdehydes are reported. The synthesized polymers are highly emissive (quantum yield of up to 50 %), as commonly observed in their 1D analogues poly(phenylene vinylene)s. The inherent well‐defined porosity (surface area ca. 1000 m2 g−1, pore diameter ca. 11 Å for the terephthaldehyde derived COF‐1) and 2D structure of these COFs also present a new set of properties and are likely responsible for the emission color, which is sensitive to the environment. COF‐1 is highly hydrophilic and reveals a dramatic macroscopic structural reorganization that has not been previously observed in framework materials.

Systematically Tuning the Electronic Structure of Gold Nanoclusters through Ligand Derivatization

By Anthony Cirri, Hanna Morales Hernández, Christina Kmiotek, Christopher J. Johnson from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

Atomically‐precise gold nanoclusters are known for their diverse geometric structures, yet comparatively little has been resolved regarding their electronic structure. Using mass‐selective UV/Vis spectroscopy and ligand derivatization, we show that the cluster electronic structure may be systematically tuned via precise chemical control over the interfacial chemi‐ and physisorptive interactions. Abstract While the ability to crystallize metal nanoclusters has revealed their geometric structure, the lack of a similarly precise measure of their electronic structure has hampered the development of synthetic design rules to precisely engineer their electronic properties. We track the evolution of highly‐resolved electronic absorption spectra of gold nanoclusters with precisely mass‐selected chemical composition in a controlled environment. Simple derivatization of the ligands yields larger spectral changes than varying the overall atomic composition of the cluster for two clusters with similar symmetry and size. The nominally metal‐localized HOMO–LUMO transition of these nanoclusters lowers in energy linearly with increasing electron donation from the exterior of the ligand shell for both cluster sizes. Very weak surface interactions, such as binding of He or N2, yield significant state‐dependent shifts, identifying states with significant interfacial character. These observations demonstrate a pathway for deliberate tuning of interfacial chemistry for chemical and technological applications.

Boron Nitride Membranes with a Distinct Nanoconfinement Effect for Efficient Ethylene/Ethane Separation

By Haozhen Dou, Bin Jiang, Mi Xu, Zhen Zhang, Guobin Wen, Feifei Peng, Aiping Yu, Zhengyu Bai, Yongli Sun, Luhong Zhang, Zhongyi Jiang, Zhongwei Chen from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

A BN membrane with a distinct nanoconfinement effect toward efficient ethylene/ethane separation is proposed and designed. It was formed by the nanoconfinement of reactive ionic liquids into the percolating nanochannels from the self‐assembly of BN nanosheets. Abstract A BN membrane with a distinct nanoconfinement effect toward efficient ethylene/ethane separation is presented. The horizontal and inclined self‐assembly of 2D BN nanosheets endow the BN membrane with abundant percolating nanochannels, and these nanochannels are further decorated by reactive ionic liquids (RILs) to tailor their sizes as well as to achieve nanoconfinement effect. The noncovalent interactions between RIL and BN nanosheets favor the ordered alignment of the cations and anions of RIL within BN nanochannels, which contributes to a fast and selective ethylene transport. The resultant membranes exhibit an unprecedented separation performance with superhigh C2H4 permeance of 138 GPU and C2H4/C2H6 selectivity of 128 as well as remarkably improved long‐term stability for 180 h, outperforming reported state‐of‐the‐art membranes.

Heteroepitaxial Growth of Multiblock Ln‐MOF Microrods for Photonic Barcodes

By Yinan Yao, Zhenhua Gao, Yuanchao Lv, Xianqing Lin, Yingying Liu, Yuxiang Du, Fengqin Hu, Yong Sheng Zhao from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

Multicolor photonic barcodes have been designed based on 1D Ln‐MOF multiblock heterostructures. The excellent heteroepitaxial growth characteristics of MOFs enable the effective modulation of the coding structures, thereby increasing the encoding capacity remarkably. The multicolor barcodes enable an efficient authentication and pave the way to hybrid MOFs for optical data recording and security labels. Abstract Micro/nanoscale multicolor barcodes with unique identifiability and a small footprint play significant roles in applications such as multiplexed labeling and tracking systems. Now, a strategy is reported to design multicolor photonic barcodes based on 1D Ln‐MOF multiblock heterostructures, where the domain‐controlled emissive colors and different block lengths constitute the fingerprint of a corresponding heterostructure. The excellent heteroepitaxial growth characteristics of MOFs enable the effective modulation of the coding structures, thereby remarkably increasing the encoding capacity. The as‐prepared multicolor barcodes enable an efficient authentication and exhibit great potential in fulfilling the functions of anti‐counterfeiting, information security, and so on. The results will pave an avenue to novel hybrid MOFs for optical data recording and security labels.

Microenvironment Engineering of Ruthenium Nanoparticles Incorporated into Silica Nanoreactors for Enhanced Hydrogenations

By Xiaomin Ren, Miao Guo, He Li, Chengbin Li, Liang Yu, Jian Liu, Qihua Yang from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

A nanoreactor modified with a phosphine ligand enabled the efficient hydrogenation of benzoic acid (BA) over Ru nanoparticles in organic solvent under mild conditions. This cannot be achieved in unmodified nanoreactors; the phosphine ligands can manipulate the adsorption strength of BA on Ru NPs. Abstract It is a challenging task to promote the activity and selectivity of a catalyst via precisely engineering the microenvironment, an important factor related with the catalytic performance of natural catalysts. Motivated by the water effect in promoting the catalytic activity explored in this work, a nanoreactor modified with phosphine ligand enabled the efficient hydrogenation of benzoic acid (BA) over Ru nanoparticles (NPs) in organic solvent under mild conditions, which cannot be achieved in unmodified nanoreactors. Both density functional theory (DFT) calculations and catalytic performance tests showed that the phosphine ligands can manipulate the adsorption strength of BA on Ru NPs by tuning the surface properties as well as preferentially interacting with the carboxyl of BA. The insights obtained in the present study provide a novel concept of nanoreactor design by anchoring ligands near catalytically active centers.

CO2 Hydrogenation on Cu/Al2O3: Role of Metal/Support Interface in Driving Activity and Selectivity of a Bifunctional Catalyst

By Erwin Lam, Juan José Corral‐Pérez, Kim Larmier, Gina Noh, Patrick Wolf, Aleix Comas‐Vives, Atsushi Urakawa, Christophe Copéret from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

More than one way: CO2 Hydrogenation on Cu/Al2O3 is studied by combining state‐of‐the art synthetic methods with operando spectroscopy and computational chemistry to elucidate possible reaction mechanisms forming CH3OH, CO, and CH3OCH3. Abstract Selective hydrogenation of CO2 into methanol is a key sustainable technology, where Cu/Al2O3 prepared by surface organometallic chemistry displays high activity towards CO2 hydrogenation compared to Cu/SiO2, yielding CH3OH, dimethyl ether (DME), and CO. CH3OH formation rate increases due to the metal–oxide interface and involves formate intermediates according to advanced spectroscopy and DFT calculations. Al2O3 promotes the subsequent conversion of CH3OH to DME, showing bifunctional catalysis, but also increases the rate of CO formation. The latter takes place 1) directly by activation of CO2 at the metal–oxide interface, and 2) indirectly by the conversion of formate surface species and CH3OH to methyl formate, which is further decomposed into CH3OH and CO. This study shows how Al2O3, a Lewis acidic and non‐reducible support, can promote CO2 hydrogenation by enabling multiple competitive reaction pathways on the oxide and metal–oxide interface.

Enhanced Anti‐Tumor Efficacy by Cascade of Reactive Oxygen Species Generation and Drug Release

By Sheng Wang, Guocan Yu, Zhantong Wang, Orit Jacobson, Li-Sen Lin, Weijing Yang, Hongzhang Deng, Zhimei He, Yuan Liu, Zhi-Yi Chen, Xiaoyuan Chen from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

Reactive oxygen species (ROS) can be used not only as a therapeutic agent for chemodynamic therapy (CDT), but also as a stimulus to activate release of anti‐tumor drugs, achieving enhanced efficacy through the combination of CDT and chemotherapy. Here we report a pH/ROS dual‐responsive nanomedicine consisting of β‐lapachone (Lap), pH‐responsive polymer and ROS‐responsive polyprodrug. In the intracellular acidic environment, the nanomedicine can realize pH‐triggered disassembly. The released Lap can efficiently generate hydrogen peroxide, which will be further converted into highly toxic hydroxyl radicals via Fenton reaction. Subsequently, through ROS‐induced cleavage of thioketal linker, doxorubicin will be released from the polyprodrug. In vivo results indicate that the cascade of ROS generation and anti‐tumor drug release can effectively inhibit tumor growth. This design of nanomedicine with cascade reactions offers a promising strategy to enhance anti‐tumor efficacy.

The Parent Diarsene HAs=AsH as side‐on bound ligand in an Iron Carbonyl Complex

By Manfred Scheer, Reinhard Rund, Gabor Balazs, Michael Bodensteiner from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

The terminal diarsene HAs=AsH ligand attracts special interest concerning its bonding relation in comparison to its isolable relative, ethene. Herein, by the methanolysis of [{Fe(CO)4}As(SiMe3)3] (1) the synthesis of [{Fe(CO)4}(eta2‐As2H2)] (2) is reported, containing a diarsene as unprecedented side‐on coordinated ligand HAs=AsH. Following this synthetic route, also the D‐labeled complex [{Fe(CO)4}(eta2‐As2D2)] (2D) could be isolated. The electronic structure and bonding situation of 2 was elucidated by DFT calculations revealing that 2 is best described as an olefin‐like complex. Moreover, the reactivity of 2 towards the Lewis acids [{M(CO)5}(thf)] (M = Cr, W), leading to the complexes [Fe(CO)4AsHW(CO)5]2 (3) and [{Fe(CO)4}2AsH{Cr(CO)5}] (4), respectively, was investigated.

Fri 03 Apr 11:30: Title to be confirmed Hosted by: John Gurdon

From All Talks (aka the CURE list). Published on Aug 19, 2019.

Title to be confirmed

Abstract not available

Hosted by: John Gurdon

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Tuning the chemistry of organic‐nitrogen compounds for promoting all‐organic anionic rechargeable batteries

By Philippe Poizot, Alia Jouhara, Eric Quarez, Franck Dolhem, Michel Armand, Nicolas Dupré from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

The ever‐increasing demand for rechargeable batteries induces significant pressure on the worldwide metal supply, depleting resources and arising cost and environmental issues. In that framework, developing the chemistry of anion‐inserting electrode organic materials could promote the fabrication of molecular (metal‐free) rechargeable batteries. However, few examples are reported because little effort has been made to develop such anionic‐ion batteries. Here we show the design of two anionic host electrode materials based on N‐substituted salts of azaaromatics (zwitterions). A combination of NMR, EDS, FTIR spectroscopies coupled with thermal analyses and single‐crystal XRD allowed a thorough structural and chemical characterization of the compounds. Thanks to a reversible electrochemical anion‐de‐insertion process at ~2.2 V vs Li+/Li, the coupling with dilithium 2,5‐(dianilino)terephthalate (Li2DAnT) as the positive electrode enabled the fabrication of the first all‐organic anionic rechargeable batteries based on crystallized host electrode materials capable of delivering a specific capacity of ~27 mAh/gelectrodes with a stable cycling over dozen of cycles (~24 Wh/kgelectrodes).

NIR‐II Driven Plasmon‐Enhanced Catalysis for Timely Supply of Oxygen to Overcome Hypoxia Induced Radiotherapy Tolerance

By Yue Yang, Mei Chen, Bingzhe Wang, Peng Wang, Yongchun Liu, Yan Zhao, Kun Li, Guosheng Song, Xiao-Bing Zhang, Weihong Tan from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

Hypoxia, as a characteristic feature of solid tumor, can significantly adversely affect the outcomes of cancer radiotherapy (RT), photodynamical therapy or chemotherapy. In this study, we have developed a novel strategy to overcome tumor hypoxia induced radiotherapy tolerance. Specifically, a novel two‐dimensional Pd@Au bimetallic core‐shell nanostructures (TPAN) was employed for the sustainable and robust production of O2 in long‐term via the catalysis of endogenous H2O2. Notably, the catalytic activity of TPAN could be enhanced via surface plasmon resonance (SPR) effect triggered by NIR‐II laser irradiation, to enhance the O2 production and thereby relieve tumor hypoxia. Thus, TPAN could enhance radiotherapy outcomes by three aspects: (i) NIR‐II laser triggered SPR enhanced the catalysis of TPAN to produce O2 for relieving tumor hypoxia; (ii) high‐Z element effect arising from Au and Pd to capture X‐ray energy within tumor; (iii) TPAN affording X‐ray, photoacoustic and NIR‐II laser derived photothermal imaging, for precisely guiding cancer therapy, so as to reduce the side effects from irradiation.

Donor‐Acceptor Nanocarbon Ensembles Significantly Boost Metal‐Free All‐pH Hydrogen Evolution Catalysis via Combined Surface and Dual Electronic Modulation

By Meijia Yang, You Zhang, Junhua Jian, Long Fang, Jing Li, Zhengsong Fang, Zhongke Yuan, Liming Dai, Xudong Chen, Dingshan Yu from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

Metal‐free nanocarbons are promising candidates as low‐cost catalysts for hydrogen evolution reactions (HER), but their inferior Gibbs free energy of hydrogen adsorption (ΔGH*) and relatively hydrophobic nature suppress the HER and their all‐pH HER catalytic potential is rarely explored. Herein, we introduce a combined surface and dual electronic modulation strategy to realize efficient robust metal‐free all‐pH HER catalysis by coupling metal‐organic‐framework derived N‐doped carbon framework (MHCF, electron acceptors) with higher‐Fermi‐level pure carbon nanotubes (CNTs, electron donors), followed by surface modification with carboxyl‐group‐rich polymer. Despite three constituents are inactive, as‐assembled ternary membranes yield superior HER performance with low overpotentials and unprecedented durability (≤ 5 % activity loss over 100 h) simultaneously at all pH values. Combined theoretical and experimental studies reveal that C adjacent to pyrrolic‐N in MHCF is the most active site and the Fermi level difference induced directional interfacial electron transfer from CNTs to MHCF coupled with N‐driven intramolecular electron transfer in MHCF synergistically optimizes ΔGH* near zero, while the polymer modulation enables local H+ enrichment in acidic media and enhanced water adsorption and activation in neutral and basic media.

Mon 27 Jan 19:30: Pioneering genetic therapies for Huntington's disease and its relevance for neurodegeneration

From All Talks (aka the CURE list). Published on Aug 19, 2019.

Pioneering genetic therapies for Huntington's disease and its relevance for neurodegeneration

An overview of antisense oligonucleotide therapies in development for neurodegenerative diseases.

There are no effective disease modifying therapies for neurodegenerative diseases such as Alzheimer’s (AD), Parkinson’s (PD), amyotrophic lateral sclerosis (ALS) or Huntington’s disease (HD). Huntington’s disease (HD) is a devastating autosomal dominantly inherited neurodegenerative disease and the genetic predictability of HD provides an opportunity for early therapeutic intervention many years before overt symptom onset and at a time when reversal or prevention of neural dysfunction may still be possible. As HD is monogenetic, fully penetrant, and characterised by a long premanifest phase, it is emerging as a potential model for studying therapeutic intervention in other neurodegenerative conditions such as Alzheimer’s or Parkinson’s disease where no preclinical diagnostic tests exist. In addition, HD manifests with a broad range of clinical symptoms and signs, many of them common to these other diseases, and involves widespread pathology throughout most of the brain involving similar protein misfolding. Understanding of HD pathogenesis is evolving, and I will present an overview of important approaches in development for targeting mutant HTT DNA and RNA , the cause of HD pathogenesis, and in particular I will present our recent successful phase 1b/2a clinical trial testing the effects of antisense oligonucleotide therapy (ASO) with RG6042 (formerly known as IONIS HTT Rx) in patients with early Huntington’s Disease and present the results of the first successful HTT -lowering drug trial (Tabrizi et al New England Journal of Medicine 2019). This study is the first to demonstrate antisense-mediated protein suppression in patients with a neurodegenerative disease. While this particular ASO holds great promise for HD, our findings have broader implications. These data suggest that antisense technology has the potential to provide disease-modifying benefits in other neurodegenerative diseases associated with aberrant production of proteins, including ALS , Alzheimer’s disease and many other diseases that currently lack adequate treatments. In my talk I will review ASO approaches in development for CNS diseases.

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Mon 11 Nov 19:30: The Next Generation of Children

From All Talks (aka the CURE list). Published on Aug 19, 2019.

The Next Generation of Children

How children with rare diseases can be helped by whole genome sequence analysis.

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Mon 28 Oct 19:30: Artificial Intelligence in Opthalmology

From All Talks (aka the CURE list). Published on Aug 19, 2019.

Artificial Intelligence in Opthalmology

The Moorfields-DeepMind Collaboration

Ophthalmology is among the most technology-driven of the all the medical specialties, with treatments utilizing high-spec medical lasers and advanced microsurgical techniques, and diagnostics involving ultra-high resolution imaging. Ophthalmology is also at the forefront of many trailblazing research areas in healthcare, such as stem cell therapy, gene therapy, and – most recently – artificial intelligence. In July 2016, Moorfields announced a formal collaboration with the world’s leading artificial intelligence company, DeepMind. This collaboration involves the sharing of >1,000,000 anonymised retinal scans with DeepMind to allow for the automated diagnosis of diseases such as age-related macular degeneration (AMD) and diabetic retinopathy (DR). In my presentation, I will describe the motivation – and urgent need – to apply deep learning to ophthalmology, the processes required to establish a research collaboration between the NHS and a company like DeepMind, the initial results of our research, and finally, why I believe that ophthalmology could be the first branch of medicine to be fundamentally reinvented through the application of artificial intelligence.

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Mon 14 Oct 19:30: Big Data Psychometrics

From All Talks (aka the CURE list). Published on Aug 19, 2019.

Big Data Psychometrics

Ethical Dilemmas for the Digital Age

Many researchers, including myself (e.g. Kosinski, Graepel & Stillwell, 2013), have published papers showing that psychological traits like personality and intelligence can be predicted from the digital footprints people leave behind when they use online services like social media. Should this capability be used in practice, and if so under what conditions? The Facebook Cambridge Analytica scandal clearly demonstrates that the public is uneasy when they feel their data was misused, but on the other hand the public also likes their data to be used to personalise recommendations and services. This talk will introduce the big data psychometrics technology and will pose some questions about how companies should use such technologies in practice.

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Electron Deficient Monomers Optimizes Nucleation and Enhances Photocatalytic Redox Activity of Carbon Nitrides

By Guigang Zhang, Minghui Liu, Tobias Heil, Spiros Zafeiratos, Aleksandr Savateev, Markus Antonietti, Xinchen Wang from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

Polymeric carbon nitride (PCN) is usually synthesized from nitrogen‐rich monomers such as cyanamide, melamine and urea, but is rather disordered in many cases. Here, a new allotrope of carbon nitride with internal heterostructures was obtained by co‐condensation of very electron poor monomers (e.g., 5‐amino‐tetrazole and nucleobases) in the presence of mild molten salts (e.g., NaCl/KCl) to mediate the polymerization kinetics and thus modulate the local structure, charge carrier properties, and most importantly the HOMO and LUMO levels. Results reveal that the as‐prepared NaK‐PHI‐A material shows excellent photo‐redox activities because of a nanometric hetero‐structure which enhances visible light absorption and promotes charge separation in the different domains.

Mon 30 Sep 19:30: Innovation and the Cambridge Cluster: Past, present and future.

From All Talks (aka the CURE list). Published on Aug 19, 2019.

Innovation and the Cambridge Cluster: Past, present and future.

Development, characteristics and challenges.

Cambridge has become synonymous with innovation but is also facing many challenges that are likely to impact its future trajectory. This presentation will be divided into three parts that will then lead to an open discussion. Firstly, the focus will be on the way in which this regional cluster has developed the capabilities to be internationally leading for innovation. Secondly, the characteristics of the present innovation cluster – and the unusual ways it works – will be explored. Finally, some of the challenges that have arisen as a result of success and the issues that need to be addressed will be presented.

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Regio‐ and Stereoselective Synthesis of Fully Substituted Silyl Enol Ethers of Ketones and Aldehydes in Acyclic Systems

By Ilan Marek from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

The regio‐ and stereoselective preparation of fully substituted and stereodefined silyl enol ethers of ketone and aldehyde are reported through an allyl‐Brook rearrangement. This fast and efficient strategy proceeds from a mixture of E and Z‐isomers of easily accessible starting materials.

Pressure‐Induced Multiphoton Excited Fluorochromic Metal–Organic Frameworks for Improving MPEF Properties

By Cheng‐Xia Chen, Shao‐Yun Yin, Zhang‐Wen Wei, Qian‐Feng Qiu, Neng‐Xiu Zhu, Ya‐Nan Fan, Mei Pan, Cheng‐Yong Su from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

Easy as 1/2/3: 1/2/3PEF (photon‐excited fluorescence) was correlated with pressure‐induced fluorochromism in MOFs. The multiphoton excited fluorochromic performance can be greatly enhanced after pressure stimulation. Abstract In multiphoton excited fluorescence (MPEF), high‐energy upconversion emission is obtained from low‐energy excitation by absorbance of two or more photons simultaneously. In a pressure‐induced fluorochromic process, the emission energy is switched by outer pressure stimuli. Now, five metal–organic frameworks containing the same ligand with simultaneous multiphoton absorption and pressure‐induced fluorochromic attributes were studied. One‐, two‐, and three‐photon excited fluorescence (1/2/3PEF) can be achieved in the frameworks, which exhibit pressure‐induced blue‐to‐yellow fluorochromism. The performances are closely dependent with the topologies, flexibilities, and packing states of the frameworks and chromophores therein. The multiphoton upconversion performance can be intensified by pressure‐related structural contraction. Over ten‐fold increment in the 2PA active cross‐section up to 2217 GM is achieved in pressed LIFM‐114 compared with the 210 GM for pristine sample at 780 nm.

Orthogonal Activation of RNA‐Cleaving DNAzymes in Live Cells by Reactive Oxygen Species

By Lu Xiao, Chunmei Gu, Yu Xiang from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

RNA‐cleaving DNAzymes containing H2O2‐responsive and HClO‐responsive modifications are orthogonally activated by these two reactive oxygen species (ROS) inside live cells. This enables precise intracellular activation of DNAzymes under oxidative stress as promising tools to study ROS‐related biological process. Abstract RNA‐cleaving DNAzymes are useful tools for intracellular metal‐ion sensing and gene regulation. Incorporating stimuli‐responsive modifications into these DNAzymes enables their activities to be spatiotemporally and chemically controlled for more precise applications. Despite the successful development of many caged DNAzymes for light‐induced activation, DNAzymes that can be intracellularly activated by chemical inputs of biological importance, such as reactive oxygen species (ROS), are still scarce. ROS like hydrogen peroxide (H2O2) and hypochlorite (HClO) are critical mediators of oxidative stress‐related cell signaling and dysregulation including activation of immune system as well as progression of diseases and aging. Herein, we report ROS‐activable DNAzymes by introducing phenylboronate and phosphorothioate modifications to the Zn2+‐dependent 8–17 DNAzyme. These ROS‐activable DNAzymes were orthogonally activated by H2O2 and HClO inside live human and mouse cells.

A Competing Hydrogen Bonding Pattern to Yield Thermo‐Thickening Supramolecular Polymer

By Virgile Ayzac, Quentin Sallembien, Matthieu Raynal, Benjamin Isare, Jacques Jestin, Laurent Bouteiller from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

An ester–bis‐urea self‐assembles into three competing rod‐like structures in non‐polar solvents. At high T, isotropic dispersions of rods are stabilized by the classical urea–urea hydrogen bonding pattern. At low T, the ester groups interfere in the hydrogen bond network and trigger a mesoscopic alignment of the rods. The transition from low to high T structure is reversible and accompanied by a viscosity increase. Abstract Introduction of competing interactions in the design of a supramolecular polymer (SP) creates pathway complexity. Ester–bis‐ureas contain both a strong bis‐urea sticker that is responsible for the build‐up of long rod‐like objects by hydrogen bonding and ester groups that can interfere with this main pattern in a subtle way. Spectroscopic (FTIR and CD), calorimetric (DSC), and scattering (SANS) techniques show that such ester–bis‐ureas self‐assemble into three competing rod‐like SPs. The previously unreported low‐temperature SP is stabilized by hydrogen bonds between the interfering ester groups and the urea moieties. It also features a weak macroscopic alignment of the rods. The other structures form isotropic dispersions of rods stabilized by the more classical urea‐urea hydrogen bonding pattern. The transition from the low‐temperature structure to the next occurs reversibly by heating and is accompanied by an increase in viscosity, a rare feature for solutions in hydrocarbons.

Unraveling the Light‐Activated Reaction Mechanism in a Catalytically Competent Key Intermediate of a Multifunctional Molecular Catalyst for Artificial Photosynthesis

By Linda Zedler, Alexander Klaus Mengele, Karl Michael Ziems, Ying Zhang, Maria Wächtler, Stefanie Gräfe, Torbjörn Pascher, Sven Rau, Stephan Kupfer, Benjamin Dietzek from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

The working gears of a photocatalyst: Using spectroelectrochemistry with UV/Vis, resonance‐Raman, and transient‐absorption spectroscopy, the reactive intermediates of the photocatalytic cycle of the photocatalyst [(tbbpy)2Ru(tpphz)Rh(Cp*)Cl]Cl(PF6)2 have been studied in detail. Photo‐induced electronic transitions limiting the catalytic efficiency have been identified and can guide structural improvements. Abstract Understanding photodriven multielectron reaction pathways requires the identification and spectroscopic characterization of intermediates and their excited‐state dynamics, which is very challenging due to their short lifetimes. To the best of our knowledge, this manuscript reports for the first time on in situ spectroelectrochemistry as an alternative approach to study the excited‐state properties of reactive intermediates of photocatalytic cycles. UV/Vis, resonance‐Raman, and transient‐absorption spectroscopy have been employed to characterize the catalytically competent intermediate [(tbbpy)2RuII(tpphz)RhICp*] of [(tbbpy)2Ru(tpphz)Rh(Cp*)Cl]Cl(PF6)2 (Ru(tpphz)RhCp*), a photocatalyst for the hydrogenation of nicotinamide (NAD‐analogue) and proton reduction, generated by electrochemical and chemical reduction. Electronic transitions shifting electron density from the activated catalytic center to the bridging tpphz ligand significantly reduce the catalytic activity upon visible‐light irradiation.

Bioinspired Unidirectional Silk Fibroin–Silver Compound Nanowire Composite Scaffold via Interface‐Mediated In Situ Synthesis

By Jingzhe Xue, Huai‐Ling Gao, Xiang‐Ying Wang, Kun‐Yu Qian, Yuan Yang, Tao He, Chuanxin He, Yang Lu, Shu‐Hong Yu from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

Inspired by nature: A composite scaffold composed of unidirectional silk and silver compound nanowires can be prepared via ice‐templated assembly and interface‐mediated in situ synthesis. The as‐prepared scaffolds show promising water disinfection activity and performance for solar‐driven water evaporation. Abstract Bioinspired unidirectional porous materials have emerged as a unique class of scaffolds for the fabrication of macroscopic nanomaterial assemblies. However, these scaffolds usually serve simply as mechanical carriers to support various building blocks. Here, we report that the unidirectional silk fibroin scaffold can not only act as a carrier, but also serve as a controllable multiscale reactor to achieve the in situ synthesis of a Ag3PO4 nanowire network anchored to ordered channels. Both the silk fibroin matrix and the interface play important roles in the nucleation and growth of the Ag3PO4 nanowires. This unidirectional composite scaffold can be used for efficient water disinfection. Furthermore, the facile chemical transformation of Ag3PO4 in the composite scaffold into Ag2S provided an analogous unidirectional composite silk scaffold that displays both efficient solar water evaporation effect and antibacterial activity. It is expected that this method can be extended to fabricate a series of silk‐based unidirectional composite scaffolds with varying functionalities.

Targeted Synthesis of a Zeolite with Pre‐established Framework Topology

By Donghui Jo, Suk Bong Hong from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

No longer hypothetical: Although many hypothetical zeolite frameworks have been proposed, none of them had yet been synthesized by a priori design. In this work, a targeted zeolite structure was successfully synthesized under excess‐fluoride conditions by combining computational predictions of organic structure‐directing agents (OSDAs) with an experimental setup. Abstract Given their great potential as new industrial catalysts and adsorbents, the search for new zeolite structures is of major importance in nanoporous materials chemistry. However, although innumerable theoretical frameworks have been proposed, none of them have been synthesized by a priori design yet. We generated a library of diazolium‐based cations inspired from the organic structure‐directing agents (OSDAs) recently reported to give two structurally related zeolites (PST‐21 and PST‐22) under highly concentrated, excess‐fluoride conditions and compared the stabilization energies of each OSDA cation in ten pre‐established hypothetical structures. A combination of the ability of the OSDA selected in this way with the excess‐fluoride approach has allowed us to crystallize PST‐30, the targeted aluminosilicate zeolite structure. We anticipate that our approach, which aims to rationally couple computational predictions of OSDAs with an experimental setup, will advance further development in the synthesis of zeolites with desired properties.

Systematic Hydrogen‐Bond Manipulations To Establish Polysaccharide Structure–Property Correlations

By Yang Yu, Theodore Tyrikos‐Ergas, Yuntao Zhu, Giulio Fittolani, Vittorio Bordoni, Ankush Singhal, Richard J. Fair, Andrea Grafmüller, Peter H. Seeberger, Martina Delbianco from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

Calling the tune: Tailor‐made cellulose oligosaccharide analogues, including methylated, deoxygenated, deoxyfluorinated, and carboxymethylated cellulose, were prepared by sequential addition of monomeric building blocks using automated glycan assembly. Seven different building blocks bearing modifications to disrupt specific hydrogen bonds enabled the three‐dimensional shapes and properties of the materials to be tuned. Abstract A dense hydrogen‐bond network is responsible for the mechanical and structural properties of polysaccharides. Random derivatization alters the properties of the bulk material by disrupting the hydrogen bonds, but obstructs detailed structure–function correlations. We have prepared well‐defined unnatural oligosaccharides including methylated, deoxygenated, deoxyfluorinated, as well as carboxymethylated cellulose and chitin analogues with full control over the degree and pattern of substitution. Molecular dynamics simulations and crystallographic analysis show how distinct hydrogen‐bond modifications drastically affect the solubility, aggregation behavior, and crystallinity of carbohydrate materials. This systematic approach to establishing detailed structure–property correlations will guide the synthesis of novel, tailor‐made carbohydrate materials.

Nickel‐Catalyzed Regioselective Hydroalkylation and Hydroarylation of Alkenyl Boronic Esters

By Srikrishna Bera, Xile Hu from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

Highly regio‐ and chemoselective nickel‐catalyzed hydroarylation and hydroalkylation reactions of alkenes were achieved by using Bpin as a directing group. The utility of the method is demonstrated by the late‐stage functionalization of natural products and drug molecules, the synthesis of an anticancer agent, and iterative syntheses. Abstract Metal hydride catalyzed hydrocarbonation reactions of alkenes are an efficient approach to construct new carbon–carbon bonds from readily available alkenes. However, the regioselectivity of hydrocarbonation remains challenging to be controlled. In nickel hydride (NiH) catalyzed hydrocarbonation, linear selectivity is most often obtained because of the relative stability of the linear Ni–alkyl intermediate over its branched counterpart. Herein, we show that the boronic pinacol ester (Bpin) group directs a Ni‐catalyzed hydrocarbonation to occur at its adjacent carbon center, resulting in formal branch selectivity. Both alkyl and aryl halides can be used as electrophiles in this hydrocarbonation, providing access to a wide range of secondary alkyl Bpin derivatives, which are valuable building blocks in synthetic chemistry. The utility of the method is demonstrated by the late‐stage functionalization of natural products and drug molecules, the synthesis of an anticancer agent, and iterative syntheses.

A Potent Halogen‐Bonding Donor Motif for Anion Recognition and Anion Template Mechanical Bond Synthesis

By Thanthapatra Bunchuay, Andrew Docker, Antonio J. Martinez‐Martinez, Paul D. Beer from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

The covalent appendage of electron deficient perfluoroaryl substituents to a bis‐iodotriazole pyridinium group produces a powerful halogen bond donor for anion recognition. Using this motif, halogen bonding anion templation is demonstrated as a highly efficient method for constructing a rotaxane in near quantitative yield, capable of strong halide binding in 50 % water containing aqueous media. Abstract The covalent attachment of electron deficient perfluoroaryl substituents to a bis‐iodotriazole pyridinium group produces a remarkably potent halogen bonding donor motif for anion recognition in aqueous media. Such a motif also establishes halogen bonding anion templation as a highly efficient method for constructing a mechanically interlocked molecule in unprecedented near quantitative yield. The resulting bis‐perfluoroaryl substituted iodotriazole pyridinium axle containing halogen bonding [2]rotaxane host exhibits exceptionally strong halide binding affinities in competitive 50 % water containing aqueous media, by a factor of at least three orders of magnitude greater in comparison to a hydrogen bonding rotaxane host analogue. These observations further champion and advance halogen bonding as a powerful tool for recognizing anions in aqueous media.

Kinetic Control of Aggregation Shape in Micellar Self‐Assembly

By Axel‐Laurenz Buckinx, Kirsten Verstraete, Evelien Baeten, Rico F. Tabor, Anna Sokolova, Neomy Zaquen, Tanja Junkers from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

Kinetically stable micelles are formed from block copolymers (BCPs) using continuous flow techniques. By altering the mixing of the organic and aqueous phase, control over micelle shape and size is achieved and verified using small angle neutron scattering. Abstract The first steps towards top‐down morphology control in micellar self‐assembly are introduced. Kinetically stable micelles are formed from block copolymers (BCPs) using continuous flow techniques by turbulent mixing of water with a THF solution of polymers. In this way, particle shape and size can be altered from spheres to ellipsoids solely via tuning of mixing parameters from a single BCP.

A Comprehensive Review of Materials with Catalytic Effects in Li–S Batteries: Enhanced Redox Kinetics

By Won‐Gwang Lim, Seoa Kim, Changshin Jo, Jinwoo Lee from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

The inherent problems of lithium–sulfur batteries may be overcome through the development of new catalytic materials designed to accelerate the redox kinetics. Recent advances in the field of catalytic materials and the mechanistic understanding of their catalytic activity are provided in this Minireview. Abstract Lithium–sulfur batteries (LSBs) are cost‐effective and high‐energy‐density batteries. However, the insulating nature of active materials, the shuttle effect, and slow redox kinetics lead to severe capacity decay and low rate capabilities. Numerous multimodal approaches have been attempted to tackle these issues and have pushed the cycle stability and energy density to higher levels. Recently, accelerating the redox kinetics using catalytic materials has been considered as a means to realize high‐performance LSBs. In this Minireview, we provide an insightful overview of the advances in the design of LSB catalytic materials and mechanistic descriptions of their catalytic activities.

Access to FeII Bis(σ‐B−H) Aminoborane Complexes through Protonation of a Borohydride Complex and Dehydrogenation of Amine‐Boranes

By Nikolaus Gorgas, Berthold Stöger, Luis F. Veiros, Karl Kirchner from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

The first synthesis and structural characterization of FeII based aminoborane complexes of the type [Fe(PNP)(H)(η2:η2‐H2B=NR2)]+ (R=H, Me) is reported. These species are formed upon protonation of the borohydride complex [Fe(PNP)(H)(η2‐BH4)] by ammonium salts NH2R2+ (R=H, Me). Abstract Herein, we report on the first synthesis and structural characterization of the iron based aminoborane complexes [Fe(PNP)(H)(η2:η2‐H2B=NR2)]+ (R=H, Me). These species are formed upon protonation of the borohydride complex [Fe(PNP)(H)(η2‐BH4)] by ammonium salts [NH2R2]+ (R=H, Me). For R=Me, the reaction proceeds via the cationic dinuclear intermediate [{Fe(PNP)(H)}2(μ2,η2:η2‐BH4)]+. A mechanism for the reaction is proposed based on DFT calculations that also indicate the final aminoborane complex as the thermodynamic product. All complexes were characterized by NMR spectroscopy, HRMS, and X‐ray crystallography.

Unconventional Metal–Framework Interaction in MgSi5

By Julia‐Maria Hübner, Wilder Carrillo‐Cabrera, Yurii Prots, Matej Bobnar, Ulrich Schwarz, Yuri Grin from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

The cage compound MgSi5 is formed under the high‐pressure high‐temperature conditions realized in a multi‐anvil device. The framework motif features two‐center two‐electron Si−Si bonds in the network and multi‐center bonding between the magnesium cage atoms and the silicon network. Abstract The silicon‐rich cage compound MgSi5 was obtained by high‐pressure high‐temperature synthesis. Initial crystal structure determination by electron diffraction tomography provided the basis for phase analyses in the process of synthesis optimization, finally facilitating the growth of single crystals suitable for X‐ray diffraction experiments. The crystal structure of MgSi5 (space group Cmme, Pearson notation oS24, a=4.4868(2) Å, b=10.1066(5) Å, and c=9.0753(4) Å) constitutes a new type of framework of four‐bonded silicon atoms forming Si15 cages enclosing the Mg atoms. Two types of smaller Si8 cages remain empty. The atomic interactions are characterized by two‐center two‐electron bonds within the silicon framework. In addition, there is evidence for multi‐center Mg−Si bonding in the large cavities of the framework and for lone‐pair‐like interactions in the smaller empty voids.

Linear End‐On Coordination Modes of CO2

By Camilo J. Viasus, Bulat Gabidullin, Sandro Gambarotta from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

A happy end‐on: A new bonding mode of CO2 in vanadium complexes is reported as a starting point for radical H‐atom abstraction. Abstract The second case of linear end‐on and evidence for an unprecedented bridging end‐on coordination mode of CO2 have been discovered for vanadium aryloxide complexes of the tetradentate ligand system (ONNO)2− (ONNO=2,4‐Me2‐2‐(OH) C6H2CH2]2N(CH2)2NMe2). The reaction of divalent (ONNO)VII (TMEDA) with CO2 and under the appropriate reaction conditions affords the trivalent (ONNO)VIII(OH)(η1‐CO2) resulting from an intermediate CO2 deoxygenation pathway followed by H‐atom abstraction from the aromatic solvent, and CO2 fixation. In contrast, the reduction of trivalent (ONNO)VIIICl(THF) with K, followed by exposure to CO2 in ethereal solvent, afforded the dinuclear [(ONNO)VII]2 (μ,η1‐CO2).

The Potential of Molybdenum Complexes Bearing Unsubstituted Heterodiatomic Group 15 Elements as Linkers in Supramolecular Chemistry

By Mehdi Elsayed Moussa, Michael Seidl, Gábor Balázs, Matthias Hautmann, Manfred Scheer from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

Self‐assembly through ligation: The reactions of tetrahedral molybdenum complexes bearing “naked” heterodiatomic heavier Group 15 elements, [Cp2Mo2(CO)4(μ,η2:η2‐PE)] (Cp=C5H5; E=As (1), Sb (2)), towards CuI halides were studied. These reactions afforded seven novel supramolecular assemblies in which 1 and 2 link CuI ions with an unprecedented donor behavior involving the P lone pair and the P−E σ‐bond. Abstract The reactions of tetrahedral molybdenum complexes bearing unsubstituted heterodiatomic Group 15 elements, [Cp2Mo2(CO)4(μ,η2:η2‐PE)] (Cp=C5H5; E=As (1), Sb (2)), with CuI halides afforded seven unprecedented neutral supramolecular assemblies. Depending on the Mo2PE units and the CuI halide, the oligomers [⟨{Cp2Mo2(CO)4}{μ4,η2:η2:η2:η1‐PE}⟩4⟨{CuX}{Cu(μ‐X)}⟩2] (E=As (X=Cl (3), Br (4)); E=Sb (X=Cl (6), Br (7))) or the 1D coordination polymers [{Cp2Mo2(CO)4}{μ4,η2:η2:η1:η1‐PAs}{Cu(μ‐I)}]n (5) and [{Cp2Mo2(CO)4}{μ4,η2:η2:η2:η1‐PSb}2{Cu(μ‐X)}3]n (X=I (8), Br (9)) are accessible. These solid‐state aggregates are the first and only examples featuring the organometallic heterodiatomic Mo2PE complexes 1 and 2 as linking moieties. DFT calculations demonstrate that complexes 1 and 2 present a unique class of mixed‐donor ligands coordinating to CuI centers via the P lone pair and the P−E σ‐bond, revealing an unprecedented coordination mode.

Dithieno[3,2‐b:2′,3′‐d]pyrrole Cored p‐Type Semiconductors Enabling 20 % Efficiency Dopant‐Free Perovskite Solar Cells

By Jie Zhou, Xinxing Yin, Zihao Dong, Amjad Ali, Zhaoning Song, Niraj Shrestha, Sandip Singh Bista, Qinye Bao, Randy J. Ellingson, Yanfa Yan, Weihua Tang from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

Cores and effect: Dithieno[3,2‐b:2′,3′‐d]pyrrole cored p‐type semiconductors are developed as dopant‐free hole‐transport materials for perovskite solar cells with an efficiency surpassing 20 %. The modification via π‐conjugation extension and N‐alkylation fine‐tunes the HOMO energy levels, hole mobility, solubility, and film‐forming characteristics. Abstract Organic p‐type semiconductors with tunable structures offer great opportunities for hybrid perovskite solar cells (PVSCs). We report herein two dithieno[3,2‐b:2′,3′‐d]pyrrole (DTP) cored molecular semiconductors prepared through π‐conjugation extension and an N‐alkylation strategy. The as‐prepared conjugated molecules exhibit a highest occupied molecular orbital (HOMO) level of −4.82 eV and a hole mobility up to 2.16×10−4 cm2 V−1 s−1. Together with excellent film‐forming and over 99 % photoluminescence quenching efficiency on perovskite, the DTP based semiconductors work efficiently as hole‐transporting materials (HTMs) for n‐i‐p structured PVSCs. Their dopant‐free MA0.7FA0.3PbI2.85Br0.15 devices exhibit a power conversion efficiency over 20 %, representing one of the highest values for un‐doped molecular HTMs based PVSCs. This work demonstrates the great potential of using a DTP core in designing efficient semiconductors for dopant‐free PVSCs.

Nature and Topology of Metal–Oxygen Binding Sites in Zeolite Materials: 17O High‐Resolution EPR Spectroscopy of Metal‐Loaded ZSM‐5

By Elena Morra, Matteo Signorile, Enrico Salvadori, Silvia Bordiga, Elio Giamello, Mario Chiesa from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

Electron and nuclear spins can be used for the structure determination of open‐shell catalytic sites in oxygen‐containing materials. A combination of selective 17O isotopic enrichment and the unique properties of open‐shell s‐state monovalent Group 12 cations are used to derive a site‐specific topological description of active sites in an MFI zeolite. Abstract Determining structural models is pivotal to the rational understanding and development of heterogeneous catalytic systems. A paradigmatic case is represented by open‐shell metals supported on oxides, where the catalytic properties crucially depend on the nature of the metal–oxygen bonds and the extent of charge and spin transfer. Through a combination of selective 17O isotopic enrichment and the unique properties of open‐shell s‐state monovalent Group 12 cations, we derive a site‐specific topological description of active sites in an MFI zeolite. We show that just a few selected sites out of all possible are populated and that the relative occupancies depend on the specific properties of the metal, and we provide maps of charge and spin transfer at the metal–oxygen interface. This approach is not restricted to zeotype materials, rather it is applicable to any catalysts supported on oxygen‐containing materials.

Glycidyl Tosylate: Polymerization of a “Non‐Polymerizable” Monomer permits Universal Post‐Functionalization of Polyethers

By Philipp Jung, Arthur D. Ziegler, Jan Blankenburg, Holger Frey from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

The monomer‐activated mechanism allows the non‐polymerizable monomer glycidyl tosylate to be copolymerized with ethylene oxide (EO) and propylene oxide (PO), yielding copolymers with 7–25 % incorporated tosylate‐moieties. Abstract Glycidyl tosylate appears to be a non‐polymerizable epoxide when nucleophilic initiators are used because of the excellent leaving group properties of the tosylate. However, using the monomer‐activated mechanism, this unusual monomer can be copolymerized with ethylene oxide (EO) and propylene oxide (PO), respectively, yielding copolymers with 7–25 % incorporated tosylate‐moieties. The microstructure of the copolymers was investigated via in situ 1H NMR spectroscopy, and the reactivity ratios of the copolymerizations have been determined. Quantitative nucleophilic substitution of the tosylate‐moiety is demonstrated for several examples. This new structure provides access to a library of functionalized polyethers that cannot be synthesized by conventional oxyanionic polymerization.

Fri 01 Nov 14:00: Title - tbc

From All Talks (aka the CURE list). Published on Aug 19, 2019.

Title - tbc

Abstract not available

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Fri 11 Oct 16:00: An Introduction to the DVRG

From All Talks (aka the CURE list). Published on Aug 19, 2019.

An Introduction to the DVRG

Abstract not available

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Organocatalytic Enantioselective Functionalization of Unactivated Indole C(sp3)‒H Bonds

By Dengke Ma, Zhihan Zhang, Min Chen, Zhenyang Lin, Jianwei Sun from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

Herein we describe a direct catalytic asymmetric functionalization of unactivated alkyl indoles using organocatalysis. In the presence of an effective chiral urea catalyst and a phosphoric acid additive, the intermolecular C‒C bond formation between alkyl indoles and trifluoropyruvates proceeded with high efficiency and enantiocontrol. Unlike previous asymmetric C(sp 3 ‒H) functionalizations of α‐azaarenes, this process does not require the use of a strong base or an electron‐deficient substrate. The excellent enantiocontrol is particularly noteworthy in view of the severe background reaction as well as the complete inability of other type of catalysts evaluated. Control experiments, kinetic studies, and DFT calculations provided important insights into the mechanism.

Wed 13 Nov 16:00: Homological representations for families of groups

From All Talks (aka the CURE list). Published on Aug 19, 2019.

Homological representations for families of groups

Braid groups have a representation theory of wild type, in the sense that there is no known classification schema. Hence it is useful to shape constructions of linear representations for such family of groups to understand its representation theory. For this purpose, Lawrence and Bigelow constructed representations of the braid group on n strands using the configuration space of m points of a n-punctured disc: namely, the braid group acts on the m-th homology group of a particular covering of the configuration space. There is actually an underlying general method to build such homological representations.

In this talk, I will present a unified functorial approach to this method for general families of groups. I will also show that, under some additional assumptions, general notions of polynomiality on functors are a useful tool to classify these representations. This is a joint work with Martin Palmer.

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An Interactive Model of Communication between Abiotic Nanodevices and Living Microorganisms

By Beatriz de Luis, Antoni Llopis-Lorente, Paola Rincón, José Gadea, Félix Sancenon, Elena Aznar, Reynaldo Villalonga, José Ramón Murguía, Ramón Martínez-Máñez from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 19, 2019.

The construction of communication models at the micro‐/nanoscale involving abiotic nanodevices and living organisms has the potential to open a wide range of applications in biomedical and communications technologies. However, this area remains almost unexplored. Here we report, as a proof of concept, a stimuli‐responsive interactive paradigm of communication between yeasts (as a model microorganism) and enzyme‐controlled Janus Au‐mesoporous silica nanoparticles. In the presence of the stimulus, the information flows from the microorganism to the nanodevice, and then returns from the nanodevice to the microorganism as a feedback.

[ASAP] Near-Infrared Imaging of Serotonin Release from Cells with Fluorescent Nanosensors

By Meshkat Dinarvand†, Elsa Neubert†‡, Daniel Meyer†, Gabriele Selvaggio†, Florian A. Mann†, Luise Erpenbeck‡, and Sebastian Kruss*† from Nano Letters: Latest Articles (ACS Publications). Published on Aug 19, 2019.

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Nano Letters
DOI: 10.1021/acs.nanolett.9b02865

[ASAP] Gate Tunable Cooperativity between Vibrational Modes

By Parmeshwar Prasad, Nishta Arora, and A. K. Naik* from Nano Letters: Latest Articles (ACS Publications). Published on Aug 19, 2019.

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Nano Letters
DOI: 10.1021/acs.nanolett.9b01219

[ASAP] Correction to Large Tunable Spin-to-Charge Conversion Induced by Hybrid Rashba and Dirac Surface States in Topological Insulator Heterostructures

By Rui Sun, Shijia Yang, Xu Yang, Eric Vetter, Dali Sun*, Na Li, Lei Su, Yan Li, Yang Li, Zi-zhao Gong, Zong-kai Xie, Kai-yue Hou, Qeemat Gul, Wei He, Xiang-qun Zhang, and Zhao-hua Cheng* from Nano Letters: Latest Articles (ACS Publications). Published on Aug 19, 2019.

Nano Letters
DOI: 10.1021/acs.nanolett.9b03326

[ASAP] Photoexcitation Induced Quantum Dynamics of Charge Density Wave and Emergence of a Collective Mode in 1T-TaS2

By Jin Zhang†‡¶, Chao Lian†¶, Mengxue Guan†‡¶, Wei Ma†‡, Huixia Fu†‡, Haizhong Guo§, and Sheng Meng*†‡? from Nano Letters: Latest Articles (ACS Publications). Published on Aug 19, 2019.

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Nano Letters
DOI: 10.1021/acs.nanolett.9b01865

[ASAP] A Three-in-One Immunotherapy Nanoweapon via Cascade-Amplifying Cancer-Immunity Cycle against Tumor Metastasis, Relapse, and Postsurgical Regrowth

By Qian Li†, Di Zhang†, Jing Zhang†, Yue Jiang†, Aixin Song‡, Zhonghao Li‡, and Yuxia Luan*† from Nano Letters: Latest Articles (ACS Publications). Published on Aug 19, 2019.

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Nano Letters
DOI: 10.1021/acs.nanolett.9b02923

[ASAP] High Affinity of Chlorin e6 to Immunoglobulin G for Intraoperative Fluorescence Image-Guided Cancer Photodynamic and Checkpoint Blockade Therapy

By Jiaojiao Xu†, Sheng Yu†, Xiaodong Wang§, Yuyi Qian†, Weishu Wu†, Sihang Zhang†, Binbin Zheng†, Guoguang Wei†, Shuai Gao†, Zhonglian Cao†, Wei Fu†, Zeyu Xiao*‡, and Wei Lu*† from ACS Nano: Latest Articles (ACS Publications). Published on Aug 19, 2019.

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ACS Nano
DOI: 10.1021/acsnano.9b03466

[ASAP] Synthesis and High-Pressure Mechanical Properties of Superhard Rhenium/Tungsten Diboride Nanocrystals

By Jialin Lei†, Shanlin Hu†, Christopher L. Turner†, Keyu Zeng†, Michael T. Yeung†, Jinyuan Yan?, Richard B. Kaner*†‡§, and Sarah H. Tolbert*†‡§ from ACS Nano: Latest Articles (ACS Publications). Published on Aug 19, 2019.

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ACS Nano
DOI: 10.1021/acsnano.9b02103

[ASAP] Super-resolution Microscopy for Nanomedicine Research

By Silvia Pujals† and Lorenzo Albertazzi*†‡ from ACS Nano: Latest Articles (ACS Publications). Published on Aug 19, 2019.

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ACS Nano
DOI: 10.1021/acsnano.9b05289

[ASAP] sp2–sp3-Hybridized Atomic Domains Determine Optical Features of Carbon Dots

By Nikita V. Tepliakov*†, Evgeny V. Kundelev†, Pavel D. Khavlyuk†, Yuan Xiong‡, Mikhail Yu. Leonov†, Weiren Zhu*¶, Alexander V. Baranov†, Anatoly V. Fedorov†, Andrey L. Rogach†‡, and Ivan D. Rukhlenko*†§ from ACS Nano: Latest Articles (ACS Publications). Published on Aug 19, 2019.

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ACS Nano
DOI: 10.1021/acsnano.9b05444

[ASAP] How Substitutional Point Defects in Two-Dimensional WS2 Induce Charge Localization, Spin–Orbit Splitting, and Strain

By Bruno Schuler*†, Jun-Ho Lee*†‡, Christoph Kastl†¶, Katherine A. Cochrane†, Christopher T. Chen†, Sivan Refaely-Abramson†?, Shengjun Yuan§, Edo van Veen?, Rafael Rolda´n?, Nicholas J. Borys#, Roland J. Koch?, Shaul Aloni†, Adam M. Schwartzberg†, D. Frank Ogletree†, Jeffrey B. Neaton*†‡¦, and Alexander Weber-Bargioni† from ACS Nano: Latest Articles (ACS Publications). Published on Aug 19, 2019.

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ACS Nano
DOI: 10.1021/acsnano.9b04611

[ASAP] Boron Nitride Nanotube Nucleation via Network Fusion during Catalytic Chemical Vapor Deposition

By Ben McLean†, Grant B. Webber‡, and Alister J. Page*† from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 19, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b03484

[ASAP] Norbornadienes: Robust and Scalable Building Blocks for Cascade “Click” Coupling of High Molecular Weight Polymers

By Andre H. St. Amant†§, Emre H. Discekici†‡§, Sophia J. Bailey†, Manuel S. Zayas†, Jung-Ah Song‡, Shelby L. Shankel†, Shay N. Nguyen†, Morgan W. Bates‡, Athina Anastasaki‡, Craig J. Hawker*†‡?, and Javier Read de Alaniz*† from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 19, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b06328

[ASAP] Crystallographic Visualization of Postsynthetic Nickel Clusters into Metal–Organic Framework

By Xiao-Ning Wang†?, Peng Zhang‡?, Angelo Kirchon‡, Jia-Luo Li‡, Wen-Miao Chen‡, Yu-Meng Zhao†, Bao Li*†, and Hong-Cai Zhou*‡§ from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 19, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b06711

[ASAP] Trapping of a Putative Intermediate in the Cytochrome c Nitrite Reductase (ccNiR)-Catalyzed Reduction of Nitrite: Implications for the ccNiR Reaction Mechanism

By Mahbbat Ali†, Natalia Stein†, Yingxi Mao†, Shahid Shahid†, Marius Schmidt‡, Brian Bennett*§, and A. Andrew Pacheco*† from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 19, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b03036

[ASAP] Ultrafast Oxidation of a Tyrosine by Proton-Coupled Electron Transfer Promotes Light Activation of an Animal-like Cryptochrome

By Fabien Lacombat†, Agathe Espagne†, Nadia Dozova†, Pascal Plaza*†, Pavel Mu¨ller*‡, Klaus Brettel‡, Sophie Franz-Badur§, and Lars-Oliver Essen*§ from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 19, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b03680

[ASAP] Iron-Catalyzed Anti-Markovnikov Hydroamination and Hydroamidation of Allylic Alcohols

By Wei Ma†, Xiaohui Zhang†, Juan Fan†, Yuxuan Liu†, Weijun Tang†, Dong Xue†, Chaoqun Li†, Jianliang Xiao*†‡, and Chao Wang*† from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 19, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b05221

[ASAP] Alkyl Chain Length-Selective Vapor-Induced Fluorochromism of Pillar[5]arene-Based Nonporous Adaptive Crystals

By Qi Li, Huangtianzhi Zhu, and Feihe Huang* from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 19, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b05054

[ASAP] Colloidal Atomic Layer Deposition with Stationary Reactant Phases Enables Precise Synthesis of “Digital” II–VI Nano-heterostructures with Exquisite Control of Confinement and Strain

By Abhijit Hazarika†, Igor Fedin†, Liang Hong‡, Jinglong Guo‡, Vishwas Srivastava†, Wooje Cho†, Igor Coropceanu†, Joshua Portner†, Benjamin T. Diroll§, John P. Philbin¶, Eran Rabani¶??, Robert Klie‡, and Dmitri V. Talapin*†§ from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 19, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b04866

[ASAP] Boosting Electrocatalytic Hydrogen Evolution Activity with a NiPt3@NiS Heteronanostructure Evolved from a Molecular Nickel–Platinum Precursor

By Chakadola Panda†#, Prashanth W. Menezes*†#, Shenglai Yao†, Johannes Schmidt‡, Carsten Walter†, Jan Niklas Hausmann†, and Matthias Driess*† from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 19, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b06530

[ASAP] Asymmetric Synthesis and Stereochemical Assignment of 12C/13C Isotopomers

By Tomoya Miura*, Takayuki Nakamuro†, Yuuya Nagata, Daisuke Moriyama, Scott G. Stewart, and Masahiro Murakami* from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 19, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b07181

Dielectric disorder in two-dimensional materials

By Alexey Chernikov from Nature Nanotechnology - Issue - nature.com science feeds. Published on Aug 19, 2019.

Nature Nanotechnology, Published online: 19 August 2019; doi:10.1038/s41565-019-0520-0

Local changes of the Coulomb interaction due to external dielectric environment fluctuations present a new type of disorder in monolayer transition-metal dichalcogenides.

Computational design of three-dimensional RNA structure and function

By Rhiju Das from Nature Nanotechnology - Issue - nature.com science feeds. Published on Aug 19, 2019.

Nature Nanotechnology, Published online: 19 August 2019; doi:10.1038/s41565-019-0517-8

Automated 3D design produces rapid and near-atomically accurate predictions of RNA tertiary structure as well as the ability to generate complex RNA machines such as functional single-stranded tethered ribosomes, and enhancement of the binding properties of small-molecule RNA aptamers.

Remotely controlled chemomagnetic modulation of targeted neural circuits

By Polina Anikeeva from Nature Nanotechnology - Issue - nature.com science feeds. Published on Aug 19, 2019.

Nature Nanotechnology, Published online: 19 August 2019; doi:10.1038/s41565-019-0521-z

Controlled delivery of neuromodulators in the brain might improve the understanding of the molecular basis of behaviour. In this letter, magnetic liposomes injected in deep brain regions release small molecules under remote magnetic stimulation, activating specific neuronal circuits in freely moving mice.

Switching magnetization with a Weyl semimetal

By Marcos H. D. Guimarães from Nature Nanotechnology - Issue - nature.com science feeds. Published on Aug 19, 2019.

Nature Nanotechnology, Published online: 19 August 2019; doi:10.1038/s41565-019-0541-8

Energy-efficient magnetization manipulation is a prerequisite for competitive spintronic devices. The Weyl semimetal WTe2 can act as a spin current source that enables magnetization switching of an adjacent ferromagnet at low power consumption and additionally induces chiral magnetism.

All-electric magnetization switching and Dzyaloshinskii–Moriya interaction in WTe2/ferromagnet heterostructures

By Hyunsoo Yang from Nature Nanotechnology - Issue - nature.com science feeds. Published on Aug 19, 2019.

Nature Nanotechnology, Published online: 19 August 2019; doi:10.1038/s41565-019-0525-8

The Weyl semimetal WTe2 possesses strong spin–orbit coupling and time-reversal-protected spin polarization in surface and bulk states. In a WTe2/permalloy heterostructure, WTe2 can act as a spin current source that enables magnetization switching at low current densities.

Organic mixed ionic–electronic conductors

By Jonathan Rivnay from Nature Materials - Issue - nature.com science feeds. Published on Aug 19, 2019.

Nature Materials, Published online: 19 August 2019; doi:10.1038/s41563-019-0435-z

Organic mixed ionic–electronic conductors

Hyaluronic acid–bilirubin nanomedicine for targeted modulation of dysregulated intestinal barrier, microbiome and immune responses in colitis

By James J. Moon from Nature Materials - Issue - nature.com science feeds. Published on Aug 19, 2019.

Nature Materials, Published online: 19 August 2019; doi:10.1038/s41563-019-0462-9

Imbalance of the gut microbiome has been implicated in numerous human diseases. Nanoparticles have now been designed to target colitis by modulating the gut microbiome, local innate immune response and restoration of the intestinal barrier function.

Programming shape using kirigami tessellations

By L. Mahadevan from Nature Materials - Issue - nature.com science feeds. Published on Aug 19, 2019.

Nature Materials, Published online: 19 August 2019; doi:10.1038/s41563-019-0452-y

Geometric analysis and constrained optimization algorithms allow for the design of kirigami patterns that can be deployed into any two- or three-dimensional shape.

Fundamentals of inorganic solid-state electrolytes for batteries

By Christian Masquelier from Nature Materials - Issue - nature.com science feeds. Published on Aug 19, 2019.

Nature Materials, Published online: 19 August 2019; doi:10.1038/s41563-019-0431-3

Solid-state batteries are attractive due to their potential safety, energy-density and cycle-life benefits. Recent progress in understanding inorganic solid electrolytes considering multiscale ion transport, electrochemical and mechanical properties, and processing are discussed.

Synthetic spin–orbit interaction for Majorana devices

By T. Kontos from Nature Materials - Issue - nature.com science feeds. Published on Aug 19, 2019.

Nature Materials, Published online: 19 August 2019; doi:10.1038/s41563-019-0457-6

A magnetic texture is used to synthetically induce a large spin–orbit interaction in a carbon nanotube, and signatures of Majorana zero modes—promising for quantum computing applications—are observed.

Biomedical and bioimaging applications of 2D pnictogens and transition metal dichalcogenides

By Martin Pumera from RSC - Nanoscale latest articles. Published on Aug 19, 2019.

Nanoscale, 2019, Advance Article
DOI: 10.1039/C9NR04658E, Minireview
Veronika Urbanová, Martin Pumera
Multifunctional platforms will play a key role and gain more prominence in the field of personalized healthcare worldwide in the near future due to the ever-increasing number of patients suffering from cancer.
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Room Temperature Ferromagnetism and Antiferromagnetism in Two-Dimensional Iron Arsenides

By Shengyuan Yang from RSC - Nanoscale latest articles. Published on Aug 19, 2019.

Nanoscale, 2019, Accepted Manuscript
DOI: 10.1039/C9NR04338A, Paper
Yalong Jiao, Weikang Wu, Fengxian Ma, Zhi-Ming Yu, Y.H. Lu, Xianlei Sheng, Yunwei Zhang, Shengyuan Yang
The discovery of two-dimensional (2D) magnetic materials with high critical temperature and intrinsic magnetic properties has attracted significant research interest. By using swarm-intelligence structure search and first-principles calculations, we predict...
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Au-Luminol Decorated Porous Carbon Nanospheres for Electrochemiluminescence Biosensing of MUC1

By Wei-Hua Huang from RSC - Nanoscale latest articles. Published on Aug 19, 2019.

Nanoscale, 2019, Accepted Manuscript
DOI: 10.1039/C9NR02190F, Paper
Jingwen Gao, Miao-Miao Chen, Wei Wen, Xiuhua Zhang, Shengfu Wang, Wei-Hua Huang
Electrochemiluminesence (ECL) nanomaterials are usually deposited compactly on the surface of electrodes, which may cause poor mass transfer of reactants and results in low ECL efficiency. In this work, we...
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Recent Advances in Nanoparticulate Biomimetic Catalysts for Combating Bacteria and Biofilms

By Youhui Lin from RSC - Nanoscale latest articles. Published on Aug 19, 2019.

Nanoscale, 2019, Accepted Manuscript
DOI: 10.1039/C9NR05054J, Minireview
Xueqing Xiong, Yanyan Huang, Changxu Lin, Xiangyang Liu, Youhui Lin
Due to the abuse of antibiotics and the tendency of bacteria to form protective biofilms, it is still highly desired but remains a great challenge to design and develop new...
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Interplay between ligand mobility and nanoparticle geometry during cellular uptake of PEGylated liposomes and bicelles

By Ying Li from RSC - Nanoscale latest articles. Published on Aug 19, 2019.

Nanoscale, 2019, Advance Article
DOI: 10.1039/C9NR02408E, Paper
Open Access Open Access
Zhiqiang Shen, Huilin Ye, Martin Kröger, Shan Tang, Ying Li
We explore the cellular uptake process of PEGylated liposomes and bicelles by investigating their membrane wrapping process using large-scale molecular dynamics simulations.
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Self-assembly of Colloids Based on Microfluidics

By Jianying Wang from RSC - Nanoscale latest articles. Published on Aug 19, 2019.

Nanoscale, 2019, Accepted Manuscript
DOI: 10.1039/C9NR06817A, Review Article
Lei Wang, Jianying Wang
Self-assembly of colloids provide a powerful way for the construction of complex multi-scale materials. Microfluidic technique possesses great potential to precisely control the assembly of micro- and nano-scale building blocks...
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Germanane synthesis with simultaneous covalent functionalization: towards highly functionalized fluorescent germananes

By Martin Pumera from RSC - Nanoscale latest articles. Published on Aug 19, 2019.

Nanoscale, 2019, Advance Article
DOI: 10.1039/C9NR04081A, Paper
Jiri Sturala, Jan Luxa, Stanislava Matějková, Zdenek Sofer, Martin Pumera
We describe exfoliation and subsequent modification of calcium germanide, which yields layered germanium materials with alkyl or aryl groups. Different organic functional group covalently derivatized layered germananes exhibit very intense fluorescence.
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3D highly efficient photonic micro concave-pit arrays for enhanced solar water splitting

By Yafei Zhang from RSC - Nanoscale latest articles. Published on Aug 19, 2019.

Nanoscale, 2019, Accepted Manuscript
DOI: 10.1039/C9NR05778A, Paper
Ming Li, Le Chen, Chao Zhou, chengchao jin, Yanjie Su, Yafei Zhang
Constructing three-dimensional (3D) photonic micro/nanostrutures is regarded as one of the most promising approaches to highly efficient photoelectrodes for solar water splitting. Here, we report the design and fabrication of...
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Silicon Nanomembrane-based Near Infrared Phototransistor with Positive and Negative Photodetections

By Yongfeng Mei from RSC - Nanoscale latest articles. Published on Aug 19, 2019.

Nanoscale, 2019, Accepted Manuscript
DOI: 10.1039/C9NR05189A, Paper
Ruobing Pan, Qinglei Guo, Jun Cao, Gaoshan Huang, Yang Wang, Yuzhou Qin, Ziao Tian, Zhenghua An, Zengfeng Di, Yongfeng Mei
Surface plasmon polariton induces hot carrier injection that enables near infrared photodetection in Si nanomembranes is of great significance for Si photonics integrated circuits. In this study, near infrared photodiode...
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The construction of a novel DNA-based comparator and its application in intelligent analysis

By Yalin Tang from RSC - Nanoscale latest articles. Published on Aug 19, 2019.

Nanoscale, 2019, Accepted Manuscript
DOI: 10.1039/C9NR05270D, Communication
Dan Huang, Guo Chen, Jiarong Miao, Yi Zhang, Xiao Lin, Die Chen, Shu Yang, Qianfan Yang, Yalin Tang
In this work, a novel and general comparator was constructed based on cascaded strand displacement reactions and DNA hybridizition and its potential in intelligently weighing the quantitative predominance of two...
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An implantable and versatile piezoresistive sensor for the monitoring of human-machine interfacing interactions and dynamical process of nerve repair

By Yun Chen from RSC - Nanoscale latest articles. Published on Aug 19, 2019.

Nanoscale, 2019, Accepted Manuscript
DOI: 10.1039/C9NR03925B, Paper
Ping Wu, Xiao Ao, Yanan Zhao, Feixiang Chen, Meifang Ke, Qiang Zhang, Jianwei Zhang, Xiaowen Shi, Xiaohua He, Yun Chen
Flexible wearable and implantable piezoresistive sensors have attracted lots of attention in the applications of healthcare monitoring, disease diagnostics, and human-machine interactions. However, the restrictive sensing range, low sensing sensitivity...
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Acceptor-Free Photomultiplication Type Organic Photodetectors

By Fujun Zhang from RSC - Nanoscale latest articles. Published on Aug 19, 2019.

Nanoscale, 2019, Accepted Manuscript
DOI: 10.1039/C9NR03552D, Paper
Jianli Miao, Mingde Du, Ying Fang, Fujun Zhang
A series of organic photodetectors (OPDs) are prepared with two donor materials as active layers, and the only difference is the weight ratio of two donors (one polymer and one...
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(Co, Mn)-doped NiSe2- diethylenetriamine (dien) nanosheets and (Co, Mn, Sn)-doped NiSe2 nanowires for high performance supercapacitor: compositional/morphological evolution and (Co, Mn)-induced electron transfer

By Yun Gong from RSC - Nanoscale latest articles. Published on Aug 19, 2019.

Nanoscale, 2019, Accepted Manuscript
DOI: 10.1039/C9NR04478G, Paper
Huamei Dan, Keyu Tao, Yang Hai, Li Liu, Yun Gong
A series of MSe2-dien (M= metal(II) ion, dien = diethylenetriamine) were grown on Ni foam(NF) based on Co(II)/Mn(II) salts with different molar ratios. It was found the free-Co sample exhibits...
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A General Approach for Lab‐to‐Manufacturing Translation on Flexible Organic Solar Cells

By Xiangchuan Meng, Lin Zhang, Yuanpeng Xie, Xiaotian Hu, Zhi Xing, Zengqi Huang, Cong Liu, Licheng Tan, Weihua Zhou, Yanming Sun, Wei Ma, Yiwang Chen from Wiley: Advanced Materials: Table of Contents. Published on Aug 18, 2019.

A general approach for lab‐to‐manufacturing translation is developed to achieve high‐performance flexible organic solar modules without obvious efficiency loss. The shear impulse during coating/printing process is firstly applied to control the morphology evolution of bulk heterojunction layer for both fullerene and nonfullerene acceptor systems. A quantitative transformation factor of shear impulse between slot‐die printing and spin‐coating is detected. Abstract The blossoming of organic solar cells (OSCs) has triggered enormous commercial applications, due to their high‐efficiency, light weight, and flexibility. However, the lab‐to‐manufacturing translation of the praisable performance from lab‐scale devices to industrial‐scale modules is still the Achilles' heel of OSCs. In fact, it is urgent to explore the mechanism of morphological evolution in the bulk heterojunction (BHJ) with different coating/printing methods. Here, a general approach to upscale flexible organic photovoltaics to module scale without obvious efficiency loss is demonstrated. The shear impulse during the coating/printing process is first applied to control the morphology evolution of the BHJ layer for both fullerene and nonfullerene acceptor systems. A quantitative transformation factor of shear impulse between slot‐die printing and spin‐coating is detected. Compelling results of morphological evolution, molecular stacking, and coarse‐grained molecular simulation verify the validity of the impulse translation. Accordingly, the efficiency of flexible devices via slot‐die printing achieves 9.10% for PTB7‐Th:PC71BM and 9.77% for PBDB‐T:ITIC based on 1.04 cm2 . Furthermore, 15 cm2 flexible modules with effective efficiency up to 7.58% (PTB7‐Th:PC71BM) and 8.90% (PBDB‐T:ITIC) are demonstrated with satisfying mechanical flexibility and operating stability. More importantly, this work outlines the shear impulse translation for organic printing electronics.

Glucose‐Responsive Insulin and Delivery Systems: Innovation and Translation

By Jinqiang Wang, Zejun Wang, Jicheng Yu, Anna R. Kahkoska, John B. Buse, Zhen Gu from Wiley: Advanced Materials: Table of Contents. Published on Aug 18, 2019.

The evolution and recent progress of the mechanism, formulation, and delivery route for glucose‐responsive insulin delivery are summarized. The perspectives and challenges for clinical translation are also discussed. This Review aims to provide fundamentals for designing desirable and applicable glucose‐responsive insulin delivery systems in the future. Abstract Type 1 and advanced type 2 diabetes treatment involves daily injections or continuous infusion of exogenous insulin aimed at regulating blood glucose levels in the normoglycemic range. However, current options for insulin therapy are limited by the risk of hypoglycemia and are associated with suboptimal glycemic control outcomes. Therefore, a range of glucose‐responsive components that can undergo changes in conformation or show alterations in intermolecular binding capability in response to glucose stimulation has been studied for ultimate integration into closed‐loop insulin delivery or “smart insulin” systems. Here, an overview of the evolution and recent progress in the development of molecular approaches for glucose‐responsive insulin delivery systems, a rapidly growing subfield of precision medicine, is presented. Three central glucose‐responsive moieties, including glucose oxidase, phenylboronic acid, and glucose‐binding molecules are examined in detail. Future opportunities and challenges regarding translation are also discussed.

Fundamentals of TiO2 Photocatalysis: Concepts, Mechanisms, and Challenges

By Qing Guo, Chuanyao Zhou, Zhibo Ma, Xueming Yang from Wiley: Advanced Materials: Table of Contents. Published on Aug 18, 2019.

The basic principles and fundamental processes of TiO2 photocatalysis are highlighted. Recent progress made on the studies of the nature of TiO2 photocatalysis, in particular whether photocatalytic reactions are driven by separated charges or by energy produced via nonadiabatic exciton decay or nonadiabatic charge recombination, is summarized and discussed in detail. Abstract Photocatalysis has been widely applied in various areas, such as solar cells, water splitting, and pollutant degradation. Therefore, the photochemical mechanisms and basic principles of photocatalysis, especially TiO2 photocatalysis, have been extensively investigated by various surface science methods in the last decade, aiming to provide important information for TiO2 photocatalysis under real environmental conditions. Recent progress that provides fundamental insights into TiO2 photocatalysis at a molecular level is highlighted. Insights into the structures of TiO2 and the basic principles of TiO2 photocatalysis are discussed first, which provides the basic concepts of TiO2 photocatalysis. Following this, details of the photochemistry of three important molecules (oxygen, water, methanol) on the model TiO2 surfaces are presented, in an attempt to unravel the relationship between charge/energy transfer and bond breaking/forming in TiO2 photocatalysis. Lastly, challenges and opportunities of the mechanistic studies of TiO2 photocatalysis at the molecular level are discussed briefly, as well as possible photocatalysis models.

Multifunctional Nanoengineered Hydrogels Consisting of Black Phosphorus Nanosheets Upregulate Bone Formation

By Zhenming Wang, Jin Zhao, Wanze Tang, Liqiu Hu, Xin Chen, Yiping Su, Chang Zou, Jianhong Wang, William W. Lu, Wanxin Zhen, Ronghua Zhang, Dazhi Yang, Songlin Peng from Wiley: Small: Table of Contents. Published on Aug 18, 2019.

Black phosphorus (BP) nanosheets–based hydrogels show excellent mechanical properties, favorable mineralization, and high bioactivity. The ultra‐high strength hydrogels are made of covalent bonds combined with a high density of polymer entanglements and hydrogen bonds. Notably, the BP nanosheets exhibit intrinsic properties for induced calcium phosphate particle formation and therefore improve the mineralization of the hydrogels. Abstract Tissue‐engineered hydrogels have received extensive attention as their mechanical properties, chemical compositions, and biological signals can be dynamically modified for mimicking extracellular matrices (ECM). Herein, the synthesis of novel double network (DN) hydrogels with tunable mechanical properties using combinatorial screening methods is reported. Furthermore, nanoengineered (NE) hydrogels are constructed by addition of ultrathin 2D black phosphorus (BP) nanosheets to the DN hydrogels with multiple functions for mimicking the ECM microenvironment to induce tissue regeneration. Notably, it is found that the BP nanosheets exhibit intrinsic properties for induced CaP crystal particle formation and therefore improve the mineralization ability of NE hydrogels. Finally, in vitro and in vivo data demonstrate that the BP nanosheets, mineralized CaP crystal nanoparticles, and excellent mechanical properties provide a favorable ECM microenvironment to mediate greater osteogenic cell differentiation and bone regeneration. Consequently, the combination of bioactive chemical materials and excellent mechanical stimuli of NE hydrogels inspire novel engineering strategies for bone‐tissue regeneration.

Self‐Amplified Drug Delivery with Light‐Inducible Nanocargoes to Enhance Cancer Immunotherapy

By Bing Feng, Bo Hou, Zhiai Xu, Madiha Saeed, Haijun Yu, Yaping Li from Wiley: Advanced Materials: Table of Contents. Published on Aug 18, 2019.

Light‐inducible prodrug nanocargoes (LINC) are reported for self‐amplified drug delivery and improved cancer immunotherapy. LINC in combination with two‐wave laser irradiation efficiently induce immunogenic cell death (ICD) and suppress the activity of indoleamine 2,3‐dioxygenase 1 (IDO‐1) of the tumor cells. Combination immunotherapy by LINC significantly inhibits tumor growth, suppresses lung metastasis, and prevents tumor recurrence by eliciting immune responses and overcoming the immunosuppressive tumor microenvironment. Abstract Chemoimmunotherapy by systemic administration of individual regimens suffers from inconsistent pharmacokinetics profiles, low tumor specificity, and severe side effects. Despite promising nanoparticle‐based codelivery approaches in therapeutics, the pathophysiological barriers of solid tumors are a hurdle for tumor accumulation and deep penetration of the drug‐loaded nanoparticles. A light‐inducible nanocargo (LINC) for immunotherapy is reported. LINC is composed of a reduction‐responsive heterodimer of photosensitizer pheophorbide A (PPa) and indoleamine 2,3‐dioxygenase 1 (IDO‐1) inhibitor, i.e., NLG919, and a light‐activatable prodrug of oxaliplatin (OXA). LINC administrated through intravenous injection is passively accumulated at the tumor site to generate near‐infrared (NIR) fluorescence signal. Under fluorescence imaging guidance, the first‐wave of NIR laser irradiation induce reactive oxygen species (ROS) generation, trigger cleavage of the polyethylene glycol (PEG) corona, and thus promote tumor retention and deep penetration of LINC. When exposed to the second‐wave NIR laser illumination, LINC efficiently elicits the immune response and promotes intratumoral infiltration of cytotoxic T lymphocytes (CTLs). Furthermore, NLG919 delivered by LINC reverses the immunosuppressive tumor microenvironment by suppressing IDO‐1 activity. Chemoimmunotherapy with LINC inhibit the tumor growth, lung metastasis, and tumor recurrence. The light‐inducible self‐amplification strategy for improved drug delivery and immunotherapy shows potential.

Additive Manufacturing of Precision Biomaterials

By Elia A. Guzzi, Mark W. Tibbitt from Wiley: Advanced Materials: Table of Contents. Published on Aug 18, 2019.

The patient‐specific design of precision biomaterials enables tailored medical devices for specific needs. The integration of enabling technologies like additive manufacturing is accelerating the translation and implementation of precision biomaterials in clinical practice. With these developments, the paradigm of precision medicine extends beyond tailored pharmaceutical treatments based on “‐omics” data to include all forms of customization in modern medicine. Abstract Biomaterials play a critical role in modern medicine as surgical guides, implants for tissue repair, and as drug delivery systems. The emerging paradigm of precision medicine exploits individual patient information to tailor clinical therapy. While the main focus of precision medicine to date is the design of improved pharmaceutical treatments based on “‐omics” data, the concept extends to all forms of customized medical care. This includes the design of precision biomaterials that are tailored to meet specific patient needs. Additive manufacturing (AM) enables free‐form manufacturing and mass customization, and is a critical enabling technology for the clinical implementation of precision biomaterials. Materials scientists and engineers can contribute to the realization of precision biomaterials by developing new AM technologies, synthesizing advanced (bio)materials for AM, and improving medical‐image‐based digital design. As the field matures, AM is poised to provide patient‐specific tissue and organ substitutes, reproducible microtissues for drug screening and disease modeling, personalized drug delivery systems, as well as customized medical devices.

Epitope Imprinting Technology: Progress, Applications, and Perspectives toward Artificial Antibodies

By Kaiguang Yang, Senwu Li, Lukuan Liu, Yuwan Chen, Wen Zhou, Jiaqi Pei, Zhen Liang, Lihua Zhang, Yukui Zhang from Wiley: Advanced Materials: Table of Contents. Published on Aug 18, 2019.

Epitope imprinting is a promising tool for generating artificial biomimetic receptors with antibody‐like specific recognition sites. Epitope‐imprinted materials are usually prepared by epitope bulk imprinting or epitope surface imprinting, which are applied to the recognition of peptides, proteins, and cells in many areas, such as biomarker detection, proteome analysis, the development of novel sensors, drug delivery, and tissue engineering. Abstract Epitope imprinting is a promising tool to generate antibody‐like specific recognition sites. Recently, because of the ease of obtaining templates, the flexibility in selecting monomers, their resistance to harsh environments, and the high specificity toward targets, epitope‐imprinted materials have attracted much attention in various fields, such as bioanalysis, clinical therapy, and pharmacy. Here, the discussion is focused on the current representative epitope imprinting technologies, including epitope bulk imprinting and epitope surface imprinting. Moreover, the application of epitope‐imprinted materials to the recognition of peptides, proteins, and cells is reviewed. Finally, the remaining challenges arising from the intrinsic properties of epitope imprinting are discussed, and future development in the field is prospected.

A GSH‐Gated DNA Nanodevice for Tumor‐Specific Signal Amplification of microRNA and MR Imaging–Guided Theranostics

By Nan Yan, Lin Lin, Caina Xu, Huayu Tian, Xuesi Chen from Wiley: Small: Table of Contents. Published on Aug 18, 2019.

A facile and smart DNA nanodevice for tumor‐responsive theranostics is demonstrated. This nanodevice efficiently inhibits the false‐positive signal in non‐tumor cells as compared with traditional methods. Moreover, this is the first nanodevice to simultaneously achieve tumor‐specific‐signal‐amplified miRNA detection and glutathione‐activated MR imaging–guided tumor chemodynamic therapy. Abstract Developing tumor‐responsive diagnosis and therapy strategies for tumor theranostics is still a challenge owing to their high accuracy and specificity. Herein, an AND logic gated–DNA nanodevice, based on the fluorescence nucleic acid probe and polymer‐modified MnO2 nanosheets, for glutathione (GSH)‐gated miRNA‐21 signal amplification and GSH‐activated magnetic resonance (MR) imaging–guided chemodynamic therapy (CDT) is reported. In the presence of overexpressed miRNA and GSH (tumor cells), the nanodevice can be in situ activated and release significantly amplified fluorescence signals and MR signals. Conversely, the fluorescence signal is quenched and MR signal remains at the background level with low miRNA and GSH (normal cells), efficiently reducing the false‐positive signals by more than 50%. Under the guide of miRNA profiling and MR imaging, the tumor‐responsive hydroxyl radical (·OH) can effectively kill tumor cells. Furthermore, the nanodevice shows catalase‐like activity and glucose oxidase–like activity with the performance of O2 production and glucose consumption. This is the first time to fabricate a tumor‐responsive theranostic DNA nanodevice with tumor‐specific signal amplification of microRNA and GSH‐activated MR imaging for CDT, potential hypoxia relief and starvation therapy, which provides a new insight for designing smart theranostic strategies.

Defect Activity in Metal–Halide Perovskites

By Silvia G. Motti, Daniele Meggiolaro, Samuele Martani, Roberto Sorrentino, Alex J. Barker, Filippo Angelis, Annamaria Petrozza from Wiley: Advanced Materials: Table of Contents. Published on Aug 18, 2019.

The photochemistry of halide‐related defects affects the optoelectronic properties of lead–halide perovskite semiconductors and their reactivity to external stimuli such as light and environmental molecules. Abstract The presence of various types of chemical interactions in metal–halide perovskite semiconductors gives them a characteristic “soft” fluctuating structure, prone to a wide set of defects. Understanding of the nature of defects and their photochemistry is summarized, which leverages the cooperative action of density functional theory investigations and accurate experimental design. This knowledge is used to describe how defect activity determines the macroscopic properties of the material and related devices. Finally, a discussion of the open questions provides a path towards achieving an educated prediction of device operation, necessary to engineer reliable devices.

A Tumor‐Microenvironment‐Activated Nanozyme‐Mediated Theranostic Nanoreactor for Imaging‐Guided Combined Tumor Therapy

By Feng Liu, Lin Lin, Ying Zhang, Yanbing Wang, Shu Sheng, Caina Xu, Huayu Tian, Xuesi Chen from Wiley: Advanced Materials: Table of Contents. Published on Aug 18, 2019.

An activatable nanozyme‐mediated theranostic nanoreactor is demonstrated. The as‐constructed nanoreactor can be specifically activated by the tumor microenvironment to turn on its photoacoustic imaging signal and photothermal therapy function, thereby leading to an efficient therapeutic outcome in combination with tumor‐triggered enhanced chemodynamic therapy. More importantly, the H2O2‐activated and acid‐enhanced properties enable the nanoreactor to be specific to tumors, leaving normal tissues unharmed. Abstract Activatable theranostic agents that can be activated by tumor microenvironment possess higher specificity and sensitivity. Here, activatable nanozyme‐mediated 2,2′‐azino‐bis (3‐ethylbenzothiazoline‐6‐sulfonic acid) (ABTS) loaded ABTS@MIL‐100/poly(vinylpyrrolidine) (AMP) nanoreactors (NRs) are developed for imaging‐guided combined tumor therapy. The as‐constructed AMP NRs can be specifically activated by the tumor microenvironment through a nanozyme‐mediated “two‐step rocket‐launching‐like” process to turn on its photoacoustic imaging signal and photothermal therapy (PTT) function. In addition, simultaneously producing hydroxyl radicals in response to the high H2O2 level of the tumor microenvironment and disrupting intracellular glutathione (GSH) endows the AMP NRs with the ability of enhanced chemodynamic therapy (ECDT), thereby leading to more efficient therapeutic outcome in combination with tumor‐triggered PTT. More importantly, the H2O2‐activated and acid‐enhanced properties enable the AMP NRs to be specific to tumors, leaving the normal tissues unharmed. These remarkable features of AMP NRs may open a new avenue to explore nanozyme‐involved nanoreactors for intelligent, accurate, and noninvasive cancer theranostics.

Single Nickel Atoms on Nitrogen‐Doped Graphene Enabling Enhanced Kinetics of Lithium–Sulfur Batteries

By Linlin Zhang, Daobin Liu, Zahir Muhammad, Fang Wan, Wei Xie, Yijing Wang, Li Song, Zhiqiang Niu, Jun Chen from Wiley: Advanced Materials: Table of Contents. Published on Aug 18, 2019.

Single Ni atoms on nitrogen‐doped graphene with a unique Ni–N4 structure are used to modify the separator of a lithium–sulfur battery to improve its electrochemical performance. The oxidized Ni state of the Ni–N4 structure not only serves as an active site for immobilizing lithium polysulfides, but also accelerates their kinetic conversion via electrocatalysis. Abstract Lithium–sulfur (Li–S) batteries have arousing interest because of their high theoretical energy density. However, they often suffer from sluggish conversion of lithium polysulfides (LiPS) during the charge/discharge process. Single nickel (Ni) atoms on nitrogen‐doped graphene (Ni@NG) with Ni–N4 structure are prepared and introduced to modify the separators of Li–S batteries. The oxidized Ni sites of the Ni–N4 structure act as polysulfide traps, efficiently accommodating polysulfide ion electrons by forming strong Sx 2−⋅⋅⋅NiN bonding. Additionally, charge transfer between the LiPS and oxidized Ni sites endows the LiPS on Ni@NG with low free energy and decomposition energy barrier in an electrochemical process, accelerating the kinetic conversion of LiPS during the charge/discharge process. Furthermore, the large binding energy of LiPS on Ni@NG also shows its ability to immobilize the LiPS and further suppresses the undesirable shuttle effect. Therefore, a Li–S battery based on a Ni@NG modified separator exhibits excellent rate performance and stable cycling life with only 0.06% capacity decay per cycle. It affords fresh insights for developing single‐atom catalysts to accelerate the kinetic conversion of LiPS for highly stable Li–S batteries.

Fe2+‐Doped Layered Double (Ni, Fe) Hydroxides as Efficient Electrocatalysts for Water Splitting and Self‐Powered Electrochemical Systems

By Xiaoyi Meng, Junxing Han, Liang Lu, Genrui Qiu, Zhong Lin Wang, Chunwen Sun from Wiley: Small: Table of Contents. Published on Aug 18, 2019.

An Fe2+‐doped NiFe(II,III)‐layered double hydroxide (LDH) is prepared by a redox reaction between Fe3+ and nickel foam. The optimized O‐NiFe(II,III)‐LDH catalyst for oxygen evolution reaction and H‐NiFe(II,III)‐LDH catalyst for hydrogen evolution reaction show a low overpotential for water splitting. It is demonstrated that water splitting devices can be driven by a self‐powered system through integrating a triboelectric nanogenerator and battery, showing a promising way to realize self‐powered electrochemical systems. Abstract Developing nonprecious electrocatalysts with superior activity and durability for electrochemical water splitting is of great interest but challenging due to the large overpotential required above the thermodynamic standard potential of water splitting (1.23 V). Here, in situ growth of Fe2+‐doped layered double (Ni, Fe) hydroxide (NiFe(II,III)‐LDH) on nickel foam with well‐defined hexagonal morphology and high crystallinity by a redox reaction between Fe3+ and nickel foam under hydrothermal conditions is reported. Benefiting from tuning the local atomic structure by self‐doping Fe2+, the NiFe(II,III)‐LDH catalyst with higher amounts of Fe2+ exhibits high activity toward oxygen evolution reaction (OER) as well as hydrogen evolution reaction (HER) activity. Moreover, the optimized NiFe(II,III)‐LDH catalyst for OER (O‐NiFe(II,III)‐LDH) and catalyst for HER (H‐NiFe(II,III)‐LDH) show overpotentials of 140 and 113 mV, respectively, at a current density of 10 mA cm−2 in 1 m KOH aqueous electrolyte. Using the catalysts for overall water splitting in two‐electrode configuration, a low overpotential of just 1.54 V is required at a benchmark current density of 10 mA cm−2. Furthermore, it is demonstrated that electrolysis of the water device can be drived by a self‐powered system through integrating a triboelectric nanogenerator and battery, showing a promising way to realize self‐powered electrochemical systems.

Chemically Exfoliated VSe2 Monolayers with Room‐Temperature Ferromagnetism

By Wei Yu, Jing Li, Tun Seng Herng, Zishen Wang, Xiaoxu Zhao, Xiao Chi, Wei Fu, Ibrahim Abdelwahab, Jun Zhou, Jiadong Dan, Zhongxin Chen, Zhi Chen, Zejun Li, Jiong Lu, Stephen J. Pennycook, Yuan Ping Feng, Jun Ding, Kian Ping Loh from Wiley: Advanced Materials: Table of Contents. Published on Aug 18, 2019.

Large size 1T‐VSe2 monolayers are successfully produced at high yield by electrochemical exfoliation of bulk crystal. To guard against air‐induced degradation, thiol molecules are introduced to passivate the VSe2 flakes, allowing the observation of robust room‐temperature ferromagnetism in monolayer VSe2. Abstract Among van der Waals layered ferromagnets, monolayer vanadium diselenide (VSe2) stands out due to its robust ferromagnetism. However, the exfoliation of monolayer VSe2 is challenging, not least because the monolayer flake is extremely unstable in air. Using an electrochemical exfoliation approach with organic cations as the intercalants, monolayer 1T‐VSe2 flakes are successfully obtained from the bulk crystal at high yield. Thiol molecules are further introduced onto the VSe2 surface to passivate the exfoliated flakes, which improves the air stability of the flakes for subsequent characterizations. Room‐temperature ferromagnetism is confirmed on the exfoliated 2D VSe2 flakes using a superconducting quantum interference device (SQUID), X‐ray magnetic circular dichroism (XMCD), and magnetic force microscopy (MFM), where the monolayer flake displays the strongest ferromagnetic properties. Se vacancies, which can be ubiquitous in such materials, also contribute to the ferromagnetism of VSe2, although density functional theory (DFT) calculations show that such effect can be minimized by physisorbed oxygen molecules or covalently bound thiol molecules.

AFM‐Based Spin‐Exchange Microscopy Using Chiral Molecules

By Amir Ziv, Abhijit Saha, Hen Alpern, Nir Sukenik, Lech Tomasz Baczewski, Shira Yochelis, Meital Reches, Yossi Paltiel from Wiley: Advanced Materials: Table of Contents. Published on Aug 18, 2019.

Local magnetic imaging at nanoscale resolution is desirable for basic studies of magnetic materials and for numerous applications. However, such local imaging is hard to achieve by means of standard magnetic force microscopy. A simple and robust method for local magnetic imaging based on short‐range spin exchange interactions realized with a chiral‐molecule‐functionalized AFM tip is presented. Abstract Local magnetic imaging at nanoscale resolution is desirable for basic studies of magnetic materials and for magnetic logic and memories. However, such local imaging is hard to achieve by means of standard magnetic force microscopy. Other techniques require low temperatures, high vacuum, or strict limitations on the sample conditions. A simple and robust method is presented for locally resolved magnetic imaging based on short‐range spin‐exchange interactions that can be scaled down to atomic resolution. The presented method requires a conventional AFM tip functionalized with a chiral molecule. In proximity to the measured magnetic sample, charge redistribution in the chiral molecule leads to a transient spin state, caused by the chiral‐induced spin‐selectivity effect, followed by the exchange interaction with the imaged sample. While magnetic force microscopy imaging strongly depends on a large working distance, an accurate image is achieved using the molecular tip in proximity to the sample. The chiral molecules' spin‐exchange interaction is found to be 150 meV. Using the tip with the adsorbed chiral molecules, two oppositely magnetized samples are characterized, and a magnetic imaging is performed. This method is simple to perform at room temperature and does not require high‐vacuum conditions.

Trimetallic Synergy in Intermetallic PtSnBi Nanoplates Boosts Formic Acid Oxidation

By Shuiping Luo, Wen Chen, Yu Cheng, Xing Song, Qilong Wu, Lanxi Li, Xiaotong Wu, Tianhao Wu, Mingrui Li, Qi Yang, Kerong Deng, Zewei Quan from Wiley: Advanced Materials: Table of Contents. Published on Aug 18, 2019.

Intermetallic PtSnBi nanoplates with tunable compositions are fabricated via a sequential “complexing–reducing–ordering” process in a one‐pot wet‐chemistry method. These Pt45Sn25Bi30 intermetallic nanoplates exhibit excellent electrocatalytic activity and outstanding long‐term stability toward the formic acid oxidation reaction, due to the efficient suppression of CO* formation and the optimization of dehydrogenation steps. Abstract Platinum is the most effective metal for a wide range of catalysis reactions, but it fails in the formic acid electrooxidation test and suffers from severe carbon monoxide poisoning. Developing highly active and stable catalysts that are capable of oxidizing HCOOH directly into CO2 remains challenging for commercialization of direct liquid fuel cells. A new class of PtSnBi intermetallic nanoplates is synthesized to boost formic acid oxidation, which greatly outperforms binary PtSn and PtBi intermetallic, benefiting from the synergism of chosen three metals. In particular, the best catalyst, atomically ordered Pt45Sn25Bi30 nanoplates, exhibits an ultrahigh mass activity of 4394 mA mg−1 Pt and preserves 78% of the initial activity after 4000 potential cycles, which make it a state‐of‐the‐art catalyst toward formic acid oxidation. Density functional theory calculations reveal that the electronic and geometric effects in PtSnBi intermetallic nanoplates help suppress CO* formation and optimize dehydrogenation steps.

Nitric‐Oxide‐Releasing Biomaterial Regulation of the Stem Cell Microenvironment in Regenerative Medicine

By Adam C. Midgley, Yongzhen Wei, Zongjin Li, Deling Kong, Qiang Zhao from Wiley: Advanced Materials: Table of Contents. Published on Aug 18, 2019.

Nitric oxide (NO), a gasotransmitter, is found to have unprecedented actions in the regulation of stem cell function and subsequent influence over the regenerative tissue microenvironment, offering an attractive solution to the limitations associated with stem cell therapy alone. Recent advances in biomaterial carriers for combined stem cell and NO therapy are assessed. Abstract Stem cell therapy has proven to be an attractive solution for the treatment of degenerative diseases or injury. However, poor cell engraftment and survival within injured tissues limits the successful use of stem cell therapy within the clinical setting. Nitric oxide (NO) is an important signaling molecule involved in various physiological processes. Emerging evidence supports NO's diverse roles in modulating stem cell behavior, including survival, migration, differentiation, and paracrine secretion of proregenerative factors. Thus, there has been a shift in research focus to concentrate efforts on the delivery of therapeutic concentration ranges of NO to the target tissue sites. Combinatory therapies utilizing biomaterials that control NO generation and support stem cell delivery can be holistic and synergistic approaches to significantly improve tissue regeneration. Here, the focus is on recent developments of various therapeutic platforms, engineered to both transport NO and to enhance stem‐cell‐mediated regeneration of damaged tissues. New and emerging revelations of how the stem cell microenvironment can be regulated by NO‐releasing biomaterials are also highlighted.

Exploiting Cofactor Versatility to Convert a FAD Dependent Baeyer−Villiger Monooxygenase into a Ketoreductase

By Jian Xu, Yongzhen Peng, Zhiguo Wang, Yujing Hu, Jiajie Fan, He Zheng, Xianfu Lin, Qi Wu from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 18, 2019.

Cyclohexanone monooxygenases (CHMOs) show very high catalytic specificity for natural Baeyer−Villiger (BV) reactions, but promiscuous reduction reactions have not been reported to date. In order to reach this goal, we focused mechanistically on the flavin adenine dinucleotide (FAD) as the cofactor of CHMOs, which can switch between oxidation and reduction states. We achieved such a novel promiscuous reduction activity of CHMOs by converting CHMOAcineto into a ketoreductase. Rational structure‐guided engineering of CHMOAcineto was implemented in order to drastically improve the catalytic reduction activity (yield up to 99%) and stereoselectivity (e.e. up to 99%).

Zinc Substitution of Cobalt in Vitamin B12 ‐ Zincobyric Acid and Zincobalamin as Luminescent Structural B12‐Mimics

By Christoph H Kieninger, Joseph A Baker, Maren Podewitz, Klaus Wurst, Steffen Jockusch, Andrew Lawrence, Evelyn Deery, Karl Gruber, Klaus Liedl, Martin J Warren, Bernhard Kräutler from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 17, 2019.

Replacing the central cobalt ion of vitamin B12 by other metals has been a long‐held aspiration within the B12‐field. Herein, we describe the synthesis from hydrogenobyric acid of zincobyric acid (Znby) and zincobalamin (Znbl), the Zn‐analogs of the natural cobalt‐corrins cobyric acid and vitamin B12, respectively. The solution structures of Znby and Znbl were studied by NMR‐spectroscopy. Single crystals of Znby were produced, providing the first X‐ray crystallographic structure of a zinc corrin. The structures of Znby and of computationally generated Znbl were found to resemble the corresponding Co(II)‐corrins, making such Zn‐corrins potentially useful for investigations of B12‐dependent processes. The singlet excited state of Znby had a short life‐time, limited by rapid intersystem crossing to the triplet state. Znby allowed the unprecedented observation of a corrin triplet (ET = 190 kJ/mol) and was found to be an excellent photo‐sensitizer for 1O2 (ΦΔ = 0.70).

Room Temperature Ultrafast Synthesis of N- and O- Rich Graphene Films with Expanded Interlayer Distance for High Volumetric Capacitance Supercapacitor

By Xiaohua Chen from RSC - Nanoscale latest articles. Published on Aug 17, 2019.

Nanoscale, 2019, Accepted Manuscript
DOI: 10.1039/C9NR06001D, Paper
Cong Huang, Aiping Hu, Yanhua Li, Haifeng Zhou, Yali Xu, Yan Zhang, Shengping Zhou, qunli tang, Chuansheng Chen, Xiaohua Chen
An electrochemical functionalization method is developed to fabricate N- and O- rich graphene films with expanded interlayer distance(F-RGO-60). Especially, the functionalization process could be completed within 60 seconds at room...
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Total Syntheses of Xiamycins A, C, F, H and Oridamycin A and Preliminary Evaluation of their Anti‐Fungal Properties

By Magnus Pfaffenbach, Ian Bakanas, Nicholas R O'Connor, Jessica L Herrick, Richmond Sarpong from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 16, 2019.

Divergent and enantiospecific total syntheses of the indolosesquiterpenoids xiamycins A, C, F, H and oridamycin A have been accomplished. The syntheses, which commence from (R)‐carvone, employ a key photoinduced benzannulation sequence to forge the carbazole moiety characteristic of these natural products. Late‐stage diversification from a common intermediate enabled the first syntheses of xiamycins C and F, and an unexpected one‐pot oxidative decarboxylation, which may prove general, led to xiamycin H. All synthetic intermediates and the natural products were tested for anti‐fungal activity. Xiamycin H emerged as an inhibitor of three agriculturally relevant fungal pathogens.

Ceria Nanoparticles Meet Hepatic Ischemia‐Reperfusion Injury: The Perfect Imperfection

By Dalong Ni, Hao Wei, Weiyu Chen, Qunqun Bao, Zachary T. Rosenkrans, Todd E. Barnhart, Carolina A. Ferreira, Yanpu Wang, Heliang Yao, Tuanwei Sun, Dawei Jiang, Shiyong Li, Tianye Cao, Zhaofei Liu, Jonathan W. Engle, Ping Hu, Xiaoli Lan, Weibo Cai from Wiley: Advanced Materials: Table of Contents. Published on Aug 16, 2019.

Although the importance of inhibiting oxidative stress is recognized for several decades, hepatic ischemia‐reperfusion injury (IRI) remains challenging to treat. Herein, the ceria nanoparticles are found to efficiently alleviate the clinical symptoms of hepatic IRI by scavenging reactive oxygen species, inhibiting activation of Kupffer cells and monocyte/macrophage cells. The released pro‐inflammatory cytokines are significantly reduced and the recruitment and infiltration of neutrophils is then inhibited. Abstract The mononuclear phagocyte system (MPS, e.g., liver, spleen) is often treated as a “blackbox” by nanoresearchers in translating nanomedicines. Often, most of the injected nanomaterials are sequestered by the MPS, preventing their delivery to the desired disease areas. Here, this imperfection is exploited by applying nano‐antioxidants with preferential liver uptake to directly prevent hepatic ischemia‐reperfusion injury (IRI), which is a reactive oxygen species (ROS)‐related disease. Ceria nanoparticles (NPs) are selected as a representative nano‐antioxidant and the detailed mechanism of preventing IRI is investigated. It is found that ceria NPs effectively alleviate the clinical symptoms of hepatic IRI by scavenging ROS, inhibiting activation of Kupffer cells and monocyte/macrophage cells. The released pro‐inflammatory cytokines are then significantly reduced and the recruitment and infiltration of neutrophils are minimized, which suppress subsequent inflammatory reaction involved in the liver. The protective effect of nano‐antioxidants against hepatic IRI in living animals and the revealed mechanism herein suggests their future use for the treatment of hepatic IRI in the clinic.

Two in One: Light as a Tool for 3D Printing and Erasing at the Microscale

By Rhiannon Batchelor, Tobias Messer, Marc Hippler, Martin Wegener, Christopher Barner‐Kowollik, Eva Blasco from Wiley: Advanced Materials: Table of Contents. Published on Aug 16, 2019.

Herein, a novel photoresist enabling the additive fabrication of 3D microstructures using one wavelength and subsequent spatially controlled cleavage of the printed resist using another wavelength is introduced. Microstructures are written upon exposure to 900 nm laser light and subsequent scanning using a laser at 700 nm wavelength allows for the selective removal of the written resist via a photocleavage reaction. Abstract The ability to selectively remove sections from 3D‐printed structures with high resolution remains a current challenge in 3D laser lithography. A novel photoresist is introduced to enable the additive fabrication of 3D microstructures at one wavelength and subsequent spatially controlled cleavage of the printed resist at another wavelength. The photoresist is composed of a difunctional acrylate cross‐linker containing a photolabile o‐nitrobenzyl ether moiety. 3D microstructures are written by photoinduced radical polymerization of acrylates using Ivocerin as photoinitiator upon exposure to 900 nm laser light. Subsequent scanning using a laser at 700 nm wavelength allows for the selective removal of the resist by photocleaving the o‐nitrobenzyl group. Both steps rely on two‐photon absorption. The fabricated and erased features are imaged using scanning electron microscopy (SEM) and laser scanning microscopy (LSM). In addition, a single wire bond is successfully eliminated from an array, proving the possibility of complete or partial removal of structures on demand.

Enhanced Light Utilization in Semitransparent Organic Photovoltaics Using an Optical Outcoupling Architecture

By Yongxi Li, Chengang Ji, Yue Qu, Xinjing Huang, Shaocong Hou, Chang‐Zhi Li, Liang‐Sheng Liao, L. Jay Guo, Stephen R. Forrest from Wiley: Advanced Materials: Table of Contents. Published on Aug 16, 2019.

An efficient and neutral colored semitransparent organic photovoltaic cell (ST‐OPV) is realized by utilizing a near‐infrared (NIR) absorbing ternary cell combined with a thin, semitransparent, high conductivity Cu‐Ag alloy electrode. A combination of optical outcoupling and antireflection coatings leads to enhanced visible transmission, while reflecting the NIR back into the cell where it is absorbed. Abstract Building‐integrated photovoltaics employing transparent photovoltaic cells on window panes provide an opportunity to convert solar energy to electricity rather than generating waste heat. Semitransparent organic photovoltaic cells (ST‐OPVs) that utilize a nonfullerene acceptor‐based near‐infrared (NIR) absorbing ternary cell combined with a thin, semitransparent, high conductivity Cu‐Ag alloy electrode are demonstrated. A combination of optical outcoupling and antireflection coatings leads to enhanced visible transmission, while reflecting the NIR back into the cell where it is absorbed. This combination of coatings results in doubling of the light utilization efficiency (LUE), which is equal to the product of the power conversion efficiency (PCE) and the average photopic transparency, compared with a conventional semitransparent cell lacking these coatings. A maximum LUE = 3.56 ± 0.11% is achieved for an ST‐OPV with a PCE = 8.0 ± 0.2% at 1 sun, reference AM1.5G spectrum. Moreover, neutral colored ST‐OPVs are also demonstrated, with LUE = 2.56 ± 0.2%, along with Commission Internationale d'Eclairage chromaticity coordinates of CIE = (0.337, 0.349) and a color rendering index of CRI = 87.

Strain‐Guided Oxidative Nanoperforation on Graphene

By Xiangbiao Liao, Baidu Zhang, Takumi Furutani, Youlong Chen, Hang Xiao, Yong Ni, Akio Yonezu, Xi Chen from Wiley: Small: Table of Contents. Published on Aug 16, 2019.

Strain patterns induced by pre‐patterned particles, is used to guide tunable, orderly and uniform perforation on 2D materials through an oxidative etching process. Nanopores nucleate selectively and expand at the bulges with high strain. The mechanism is uncovered using reactive molecular dynamics and theoretical models. Experiments of graphene on SiO2 nanoparticles/SiO2 substrates verify the feasibility of such strain‐guided perforation. Abstract Increased applications of nanoporous graphene in nanoelectronics and membrane separations require ordered and precise perforation of graphene, whose scalablility and time/cost effectiveness represent a significant challenge in existing nanoperforation methods, such as catalytical etching and lithography. A strain‐guided perforation of graphene through oxidative etching is reported, where nanopores nucleate selectively at the bulges induced by the prepatterned nanoprotrusions underneath. Using reactive molecular dynamics and theoretical models, the perforation mechanisms are uncovered through the relationship between bulge‐induced strain and enhanced etching reactivity. Parallel experiments of chemical vapor deposition (CVD) of graphene on SiO2 NPs/SiO2 substrates verify the feasibility of such strain‐guided perforation and evolution of pore size by exposure of varied durations to oxygen plasma. This scalable method can be feasibly applied to a broad variety of 2D materials (e.g., graphene and h‐boron nitride) and nanoprotrusions (e.g., SiO2 and C60 nanoparticles), allowing rational fabrication of 2D material‐based devices.

Unveiling the Secret, Dark, and Short Life of a Vibronic State in a Boron Difluoride Formazanate Dye

By Adyn Melenbacher, Jasveer S. Dhindsa, Joe B. Gilroy, Martin J Stillman from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 16, 2019.

Boron difluoride (BF2) formazanate dyes are contenders for molecular species that exhibit a large Stokes shift and bright red emission. Excitation of 3‐cyanoformazanate complexes with 10 μs wide pulses of specific wavelengths resulted in strong luminescence at 663 nm at both room temperature in solution and at 77 K. Analysis of the short‐lived excitation spectrum from this luminescence shows that it arises from a vibronic manifold of a higher lying excited state. This dark state relaxes to the emitting state over 10 µs. TD‐DFT calculations of the two lowest energy excited states show that the relaxed geometries are planar for S1 but highly distorted in S2. The specific time‐ and wavelength‐dependence of the excitation profile provides a unique optical encryption capability through the comparison of emission intensities between adjacent vibronic bands only accessible in the 0 –12 μs time domain.

Room‐Temperature Cubic Phase Crystallization and High Stability of Vacuum‐Deposited Methylammonium Lead Triiodide Thin Films for High‐Efficiency Solar Cells

By Francisco Palazon, Daniel Pérez‐del‐Rey, Benedikt Dänekamp, Chris Dreessen, Michele Sessolo, Pablo P. Boix, Henk J. Bolink from Wiley: Advanced Materials: Table of Contents. Published on Aug 16, 2019.

Vacuum‐deposited methylammonium lead iodide can adopt a perovskite structure with a stable cubic lattice at room temperature. Reducing the metallic salt evaporation rate leads to a tetragonal phase structure. This room‐temperature cubic perovskite circumvents the tetragonal to cubic phase transition resulting at ≈55 °C, and leads to photovoltaic devices with efficiencies above 19%. Abstract Methylammonium lead triiodide (MAPI) has emerged as a high‐performance photovoltaic material. Common understanding is that at room temperature, it adopts a tetragonal phase and it only converts to the perfect cubic phase around 50–60 °C. Most MAPI films are prepared using a solution‐based coating process, yet they can also be obtained by vapor‐phase deposition methods. Vapor‐phase‐processed MAPI films have significantly different characteristics than their solvent‐processed analogous, such as relatively small crystal‐grain sizes and short excited‐state lifetimes. However, solar cells based on vapor‐phase‐processed MAPI films exhibit high power‐conversion efficiencies. Surprisingly, after detailed characterization it is found that the vapor‐phase‐processed MAPI films adopt a cubic crystal structure at room temperature that is stable for weeks, even in ambient atmosphere. Furthermore, it is demonstrated that by tuning the deposition rates of both precursors during codeposition it is possible to vary the perovskite phase from cubic to tetragonal at room temperature. These findings challenge the common belief that MAPI is only stable in the tetragonal phase at room temperature.

Breaking Reciprocity with Space‐Time‐Coding Digital Metasurfaces

By Lei Zhang, Xiao Qing Chen, Rui Wen Shao, Jun Yan Dai, Qiang Cheng, Giuseppe Castaldi, Vincenzo Galdi, Tie Jun Cui from Wiley: Advanced Materials: Table of Contents. Published on Aug 16, 2019.

Space‐time‐coding digital metasurfaces are designed to break Lorentz reciprocity, via anomalous reflections accompanied by frequency conversions. A proof‐of‐concept validation is provided via measurements at microwave frequencies. This concept sets the stage for “on‐demand” realization of nonreciprocal effects, in programmable or reconfigurable fashions, with possible applications in frequency conversion, Doppler frequency illusion, optical isolation, and unidirectional transmission. Abstract Metasurfaces are artificially engineered ultrathin structures that can finely tailor and control electromagnetic wavefronts. There is currently a strong interest in exploring their capability to lift some fundamental limitations dictated by Lorentz reciprocity, which have strong implications in communication, heat management, and energy harvesting. Time‐varying approaches have emerged as attractive alternatives to conventional schemes relying on magnetic or nonlinear materials, but experimental evidence is currently limited to devices such as circulators and antennas. Here, the recently proposed concept of space‐time‐coding digital metasurfaces is leveraged to break reciprocity. Moreover, it is shown that such nonreciprocal effects can be controlled dynamically. This approach relies on inducing suitable spatiotemporal phase gradients in a programmable way via digital modulation of the metasurface‐elements' phase repsonse, which enable anomalous reflections accompanied by frequency conversions. A prototype operating at microwave frequencies is designed and fabricated for proof‐of‐concept validation. Measured results are in good agreement with theory, hence providing the first experimental evidence of nonreciprocal reflection effects enabled by space‐time‐modulated digital metasurfaces. The proposed concept and platform set the stage for “on‐demand” realization of nonreciprocal effects, in programmable or reconfigurable fashions, which may find several promising applications, including frequency conversion, Doppler frequency illusion, optical isolation, and unidirectional transmission.

Thu 05 Sep 15:00: Clustering insomnia pattern and learning sleep quality from daily logs

From All Talks (aka the CURE list). Published on Aug 16, 2019.

Clustering insomnia pattern and learning sleep quality from daily logs

Abstract:

Precision psychiatry is a new research field that uses advanced data mining over a wide range of neural, behavioral, psychological, and physiological data sources for classification of mental health conditions. The talk will present a computational framework for predicting sleep efficiency of insomnia sufferers. A smart band experiment is conducted to collect heterogeneous data, including sleep records, daily activities, and demographics, whose missing values are imputed via Improved Generative Adversarial Imputation Networks (Imp-GAIN). Equipped with the imputed data, we predict sleep efficiency of individual users with a proposed interpretable LSTM -Attention (LA Block) neural network model. We also propose a model, Pairwise Learning-based Ranking Generation (PLRG), to rank users with high insomnia potential in the next day. We discuss the implications of our findings from the perspective of a psychiatric practitioner. Our computational framework can be used for other applications that analyze and handle noisy and incomplete time-series human activity data in the domain of precision psychiatry.

Bio:

Sungkyu (Shaun) Park is a Ph.D. candidate in the Graduate School of Culture Technology at KAIST . He is interested in understanding human behaviors and psychiatric disorders in the wild through the lens of large-scale data. His research focuses on techniques for developing mobile/wearable applications to retrieve data and for developing interpretable prediction models on mental health domains. He has interned at Nokia Bell Labs, Cambridge this summer and owned a startup aiming to launch an intervention app for insomnia, developed based on the current research.

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Three‐Phase Photocatalysis for the Enhanced Selectivity and Activity of CO2 Reduction on Hydrophobic Surface

By Ang Li, Qian Cao, Guangye Zhou, Bernhard V. K. J. Schmidt, Wenjin Zhu, Xintong Yuan, Hailing Huo, Jinlong Gong, Markus Antonietti from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 16, 2019.

The photocatalytic CO2 reduction reaction (CRR) represents a promising route for the clean utilization of stranded renewable electricity, while poor selectivity resulting from the competing hydrogen evolution reaction (HER) in aqueous solution limits its practical applicability. In the present contribution we fabricate a photocatalyst with hydrophobic surfaces, facilitating an efficient three‐phase contact of CO2 (gas), H2O (liquid) and catalyst (solid). Thus, concentrated CO2 molecules in the gas phase are able to touch the catalyst surface directly, which can overcome the mass transfer limitations of CO2, inhibit the HER because of lowering cater contacts, and overall enhance CRR. Even when loaded with platinum nanoparticles, one of the most efficient HER promotion cocatalysts, the three‐phase photocatalyst can still keep a selectivity of 87.9%. Overall, three‐phase photocatalysis provides a general and reliable method to enhance the competitiveness of CRR.

Shedding Light on the Trehalose‐Enabled Mucopermeation of Nanoparticles with Label‐Free Raman Spectroscopy

By Soumik Siddhanta, Sourav Bhattacharjee, Sabine M. Harrison, Dimitri Scholz, Ishan Barman from Wiley: Small: Table of Contents. Published on Aug 16, 2019.

Overcoming the mucosal barrier has been a challenge for several nanotherapeutic agents. This study reports a trehalose‐mediated method for enhanced mucopermeation of nanoparticles, which can be harnessed for drug‐delivery and label‐free imaging applications. Abstract Nanoparticle‐based drug delivery systems have attracted significant interest owing to their promise as tunable platforms that offer improved intracellular release of cargo therapeutics. However, significant challenges remain in maintaining the physiological stability of the mucosal matrix due to the nanoparticle‐induced reduction in the matrix diffusivity and promotion of mucin aggregation. Such aggregation also adversely impacts the permeability of the nanoparticles, and thus, diminishes the efficacy of nanoparticle‐based formulations. Here, an entirely complementary approach is proposed to the existing nanoparticle functionalization methods to address these challenges by using trehalose, a naturally occurring disaccharide that offers exceptional protein stabilization. Plasmon‐enhanced Raman spectroscopy and far‐red fluorescence emission of the plasmonic silver nanoparticulate clusters are harnessed to create a unique dual‐functional, aggregating, and imaging agent that obviates the need of an additional reporter to investigate mucus–nanoparticle interactions. These spectroscopy‐based density mapping tools uncover the mechanism of mucus–nanoparticle interactions and establish the protective role of trehalose microenvironment in minimizing the nanoparticle aggregation. Thus, in contrast to the prevailing belief, these results demonstrate that nonfunctionalized nanoparticles may rapidly penetrate through mucus barriers, and by leveraging the bioprotectant attributes of trehalose, an in vivo milieu for efficient mucosal drug delivery can be generated.

Triphenylene‐Derived Electron Acceptors and Donors on Ag(111): Formation of Intermolecular Charge‐Transfer Complexes with Common Unoccupied Molecular States

By Kathrin Müller, Nico Schmidt, Stefan Link, René Riedel, Julian Bock, Walter Malone, Karima Lasri, Abdelkader Kara, Ulrich Starke, Milan Kivala, Meike Stöhr from Wiley: Small: Table of Contents. Published on Aug 16, 2019.

Electron acceptor and donor molecules are studied on Ag(111). The acceptor molecules show a strong interaction with the silver, while the donors are only weakly interacting with the surface. Mixing both molecules leads to the formation of a molecular charge‐transfer complex and a common unoccupied state, which was neither found for the pure donor nor for the pure acceptor layers. Abstract Over the past years, ultrathin films consisting of electron donating and accepting molecules have attracted increasing attention due to their potential usage in optoelectronic devices. Key parameters for understanding and tuning their performance are intermolecular and molecule–substrate interactions. Here, the formation of a monolayer thick blend of triphenylene‐based organic donor and acceptor molecules from 2,3,6,7,10,11‐hexamethoxytriphenylene (HAT) and 1,4,5,8,9,12‐hexaazatriphenylenehexacarbonitrile (HATCN), respectively, on a silver (111) surface is reported. Scanning tunneling microscopy and spectroscopy, valence and core level photoelectron spectroscopy, as well as low‐energy electron diffraction measurements are used, complemented by density functional theory calculations, to investigate both the electronic and structural properties of the homomolecular as well as the intermixed layers. The donor molecules are weakly interacting with the Ag(111) surface, while the acceptor molecules show a strong interaction with the substrate leading to charge transfer and substantial buckling of the top silver layer and of the adsorbates. Upon mixing acceptor and donor molecules, strong hybridization occurs between the two different molecules leading to the emergence of a common unoccupied molecular orbital located at both the donor and acceptor molecules. The donor acceptor blend studied here is, therefore, a compelling candidate for organic electronics based on self‐assembled charge‐transfer complexes.

Highly Uniform and Low Hysteresis Piezoresistive Pressure Sensors Based on Chemical Grafting of Polypyrrole on Elastomer Template with Uniform Pore Size

By Jinwon Oh, Jin‐Oh Kim, Yunjoo Kim, Han Byul Choi, Jun Chang Yang, Serin Lee, Mikhail Pyatykh, Jung Kim, Joo Yong Sim, Steve Park from Wiley: Small: Table of Contents. Published on Aug 16, 2019.

Piezoresistive sensors with high uniformity and low hysteresis are fabricated via chemically grafting a conductive polymer on the surface of an elastomer template with uniform pore size and arrangement. Finite element analysis confirms the importance of pore size uniformity in sensor uniformity. Abstract Sensor‐to‐sensor variability and high hysteresis of composite‐based piezoresistive pressure sensors are two critical issues that need to be solved to enable their practical applicability. In this work, a piezoresistive pressure sensor composed of an elastomer template with uniformly sized and arranged pores, and a chemically grafted conductive polymer film on the surface of the pores is presented. Compared to sensors composed of randomly sized pores, which had a coefficient of variation (CV) in relative resistance change of 69.65%, our sensors exhibit much higher uniformity with a CV of 2.43%. This result is corroborated with finite element simulation, which confirms that with increasing pore size variability, the variability in sensor characteristics also increases. Furthermore, our devices exhibit negligible hysteresis (degree of hysteresis: 2%), owing to the strong chemical bonding between the conductive polymer and the elastomer template, which prevents their relative sliding and displacement, and the porosity of the elastomer that enhances elastic behavior. Such features of the sensor render it highly feasible for various practical applications in the near future.

Additive Manufacturing of Nanostructures That Are Delicate, Complex, and Smaller than Ever

By Andrew J. Gross, Katia Bertoldi from Wiley: Small: Table of Contents. Published on Aug 16, 2019.

Subtractive post‐processing can overcome fabrication limitations of two‐photon polymerization. Two techniques are demonstrated which exploit the combination of controlled material removal with oxygen plasma etching and the geometric freedom of additive manufacturing. In the first, features are modified by the plasma to reach smaller dimensions, while in the second sacrificial material is removed to realize exceedingly delicate small scale structures. Abstract Additive manufacturing with two‐photon polymerization (TPP) has opened new opportunities for the rapid fabrication of 3D structures with sub‐micrometer resolution, but there are still many fabrication constraints associated with this technique. This study details a postprocessing method utilizing oxygen‐plasma etching to increase the capabilities of TPP. Underutilized precision in the typical fabrication process allows this subtractive technique to dramatically reduce the minimum achievable feature size. Moreover, since the postprocessing occurs in a dry environment, high aspect ratio features that cannot survive the typical fabrication route can also be achieved. Finally, it is shown that the technique also provides a pathway to realize structures that otherwise are too delicate to be fabricated with TPP, as it enables to introduce temporary support material that can be removed with the plasma. As such, the proposed approach grants access to a massively expanded design domain, providing new capabilities that are long sought in many fields, including optics, biology, robotics, and solid mechanics.

Ultraflexible and Lightweight Bamboo‐Derived Transparent Electrodes for Perovskite Solar Cells

By Kaiping Zhu, Zheng Lu, Shan Cong, Guanjian Cheng, Peipei Ma, Yanhui Lou, Jianning Ding, Ningyi Yuan, Mark H. Rümmeli, Guifu Zou from Wiley: Small: Table of Contents. Published on Aug 16, 2019.

Biodegradable and biocompatible transparent conductive electrodes are fabricated from bamboo for flexible perovskite solar cells. After extensive mechanical tests, including bending and crumpling tests, they still exhibit excellent electrical performance and negligible decay. The bamboo‐based bioelectrode perovskite solar cell shows a record power conversion efficiency of 11.68%, maintaining over 70% of initial power conversion efficiency after the bending tests. Abstract Wearable devices are mainly based on plastic substrates, such as polyethylene terephthalate and polyethylene naphthalate, which causes environmental pollution after use due to the long decomposition periods. This work reports on the fabrication of a biodegradable and biocompatible transparent conductive electrode derived from bamboo for flexible perovskite solar cells. The conductive bioelectrode exhibits extremely flexible and light‐weight properties. After bending 3000 times at a 4 mm curvature radius or even undergoing a crumpling test, it still shows excellent electrical performance and negligible decay. The performance of the bamboo‐based bioelectrode perovskite solar cell exhibits a record power conversion efficiency (PCE) of 11.68%, showing the highest efficiency among all reported biomass‐based perovskite solar cells. It is remarkable that this flexible device has a highly bendable mechanical stability, maintaining over 70% of its original PCE during 1000 bending cycles at a 4 mm curvature radius. This work paves the way for perovskite solar cells toward comfortable and environmentally friendly wearable devices.

Growth of Ultraflat PbI2 Nanoflakes by Solvent Evaporation Suppression for High‐Performance UV Photodetectors

By Han Xiao, Tao Liang, Mingsheng Xu from Wiley: Small: Table of Contents. Published on Aug 16, 2019.

The growth of ultraflat PbI2 nanoflakes is realized by solvent evaporation suppression. Optimized surface topography endows superior performance to PbI2‐based photodetectors, including a high responsivity of 0.51 A W−1, a high detectivity of 4.0 × 1010 Jones, a high external quantum efficiency of 168.9%, a rapid rise time of 14.1 ms, and a decay time of 31.0 ms. Abstract 2D lead iodide (PbI2) is attracting great interest due to its great potential in the application of UV photodetectors. In this work, a facile solution‐based method is developed to synthesize ultraflat PbI2 nanoflakes for high‐performance UV photodetectors. By maintaining at proximate room temperature and adding an evaporation suppression solvent for slow‐rate crystal growth, high‐quality PbI2 nanoflakes with an ultraflat surface are obtained. The UV photodetectors based on 2D PbI2 nanoflakes exhibit a high photoresponsivity of 0.51 A W−1, a high detectivity of 4.0 × 1010 Jones, a high external quantum efficiency (EQE) of 168.9%, and a rapid response speed including a rise time of 14.1 ms and a decay time of 31.0 ms. The balanced and excellent photodetector performance of these devices paves the road for practical UV photodetection based on 2D PbI2 nanoflakes.

Strain‐Stabilized Ceramic‐Sulfide Electrolytes

By William Fitzhugh, Fan Wu, Luhan Ye, Haoqing Su, Xin Li from Wiley: Small: Table of Contents. Published on Aug 16, 2019.

A theoretical framework for describing the mechano‐electrochemical coupling in constrained sulfide‐ceramic solid electrolytes is derived. The metastability of Li10GeP2S12 is expanded such that the oxidation onset increases from an intrinsic 2.1 V to nearly 4 V. An LiCoO2‐Li4Ti5O12 full‐cell all‐solid‐state battery is constructed using such techniques to demonstrate the capability of this approach. Abstract Ceramic‐sulfide solid electrolytes are a promising material system for enabling solid‐state batteries. However, one challenge that remains is the discrepancy in the reported electrochemical stability. Recent work has suggested that it may be due to the sensitivity of ceramic sulfides to mechanically induced stability. Small changes in ceramic‐sulfide microstructure, for example, have been shown to cause substantial differences in the electrochemical stability. In this work, a rigorous theoretical framework is constructed to enable the simulation of such mechanically induced stability for a generalized constraint mechanism. It is shown that the susceptibility for voltage widening in ceramic sulfides can be significantly influenced by the choice of different decay morphology models. This results in a less intrusive microstructure requirement for improved stability, which stems from the tendency of sulfides to decay via inclusions rather than homogeneously. This predicted decay morphology is experimentally confirmed. Li10GeP2S12 is stabilized by a thin amorphous shell, which prior models predict is too thin for stabilization. The generality of this framework is discussed in light of stabilization methods beyond microstructure, such as on the battery cell level. The relation of our picture to the observed lithium metal formation in ceramic sulfides is also discussed.

Two‐Photon Vertical‐Flow Lithography for Microtube Synthesis

By Jonas Lölsberg, Arne Cinar, Daniel Felder, Georg Linz, Suzana Djeljadini, Matthias Wessling from Wiley: Small: Table of Contents. Published on Aug 16, 2019.

Continuous real‐time synthesis of free‐standing porous microtubes is demonstrated using two‐photon lithography inside a microfluidic chip. Precise fluid‐flow control and simultaneous optical monitoring during high‐resolution direct laser writing reveal rigorous control over the complex microtube morphology and surface topology. This generic high‐resolution method generates thin‐walled high aspect ratio microtubes with a tunable diameter and pore size. Abstract Two‐photon vertical‐flow lithography is demonstrated for synthesis of complex‐shaped polymeric microtubes with a high aspect ratio (>100:1). This unique microfluidic approach provides rigorous control over the morphology and surface topology to generate thin‐walled (

Formation of Single Micro‐ and Nanowires with Extreme Aspect Ratios in Microfluidic Channels

By Mario Lenz, Bernhard Sebastian, Petra S. Dittrich from Wiley: Small: Table of Contents. Published on Aug 16, 2019.

Formation of single AuTTF micro‐ and nanowires in poly(dimethylsiloxane) (PDMS) microfluidic devices is presented. The structure is a result of the redox reaction between gold(III) ions and tetrathiafulvalene (TTF). The advantages of selective permeability of PDMS for TTF and advanced microfluidic chip design is demonstrated and applied to control number and orientation of structural growth. Abstract Shown here is the site‐specific formation of single extraordinarily long metal–organic micro‐ and nanowires using a microfluidic device made of poly(dimethylsiloxane) (PDMS). This approach exploits two concepts, i) the diffusion of organic precursor molecules through PDMS and ii) the use of microfluidic channels as a growth template. To initiate wire formation, metal and organic precursor solutions are filled into different supply channels that are separated by PDMS. As the precursor diffuses through PDMS, and thereby infiltrates the adjacent channel, the growth of micro‐ and nanowires starts at the side walls of this adjacent channel. The formation yields single wires with sizes ranging from several hundreds of micrometers to millimeters at diameters of 0.5–2 µm. The principles of this formation pathway are demonstrated with the reaction of tetrathiafulvalene (TTF) and gold(III) ions that yields Au‐TTF wires. The influence of various reaction parameters including the choice of solvents and the chip fabrication protocol on the reaction are evaluated. Based on these findings, a further microfluidic device design with orthogonally arranged channels is developed, and the formation of single wires in a channel‐defined pattern is demonstrated. Moreover, the possibility of pulsed precursor supply allows for advanced control over the growth of the wires.

Guiding the Morphology of Amyloid Assemblies by Electrostatic Capping: from Polymorphic Twisted Fibrils to Uniform Nanorods

By Ximena Zottig, Soultan Al‐Halifa, Margaryta Babych, Noé Quittot, Denis Archambault, Steve Bourgault from Wiley: Small: Table of Contents. Published on Aug 16, 2019.

Amyloid structures constitute promising proteinaceous materials and nanoparticles for different applications, although their usage is still limited by their intrinsic polymorphism. In this study, electrostatic repulsions between peptide N‐terminus are exploited to modulate the supramolecular architecture of amyloid assemblies. By tuning the charge and the strength of the capping unit, different mesoscopic morphologies are obtained, from long fibrils to nanorods. Abstract Peptides that self‐assemble into cross‐β‐sheet amyloid structures constitute promising building blocks to construct highly ordered proteinaceous materials and nanoparticles. Nevertheless, the intrinsic polymorphism of amyloids and the difficulty of controlling self‐assembly currently limit their usage. In this study, the effect of electrostatic interactions on the supramolecular organization of peptide assemblies is investigated to gain insights into the structural basis of the morphological diversities of amyloids. Different charged capping units are introduced at the N‐terminus of a potent β‐sheet‐forming sequence derived from the 20–29 segment of islet amyloid polypeptide, known to self‐assemble into polymorphic fibrils. By tuning the charge and the electrostatic strength, different mesoscopic morphologies are obtained, including nanorods, rope‐like fibrils, and twisted ribbons. Particularly, the addition of positive capping units leads to the formation of uniform rod‐like assemblies, with lengths that can be modulated by the charge number. It is proposed that electrostatic repulsions between N‐terminal positive charges hinder β‐sheet tape twisting, leading to a unique control over the size of these cytocompatible nanorods by protofilament growth frustration. This study reveals the high susceptibility of amyloid formation to subtle chemical modifications and opens to promising strategies to control the final architecture of proteinaceous assemblies from the peptide sequence.

A Triode Device with a Gate Controllable Schottky Barrier: Germanium Nanowire Transistors and Their Applications

By Che‐Yi Lin, Chao‐Fu Chen, Yuan‐Ming Chang, Shih‐Hsien Yang, Ko‐Chun Lee, Wen‐Wei Wu, Wen‐Bin Jian, Yen‐Fu Lin from Wiley: Small: Table of Contents. Published on Aug 16, 2019.

Nanowire (NW) transistors based on a Cu3Ge/Ge/Cu3Ge heterostructure show ambipolar transport behavior with large current modulation. Quasistatic and dynamic electrical measurements indicate that the ambipolarity arises from the formation of tunable barriers. The transistor is used to realize both binary‐signal and data‐storage functions. This work offers a valuable direction for creating future electronics based on NW transistors. Abstract Electrical contacts often dominate charge transport properties at the nanoscale because of considerable differences in nanoelectronic device interfaces arising from unique geometric and electrostatic features. Transistors with a tunable Schottky barrier between the metal and semiconductor interface might simplify circuit design. Here, germanium nanowire (Ge NW) transistors with Cu3Ge as source/drain contacts formed by both buffered oxide etching treatments and rapid thermal annealing are reported. The transistors based on this Cu3Ge/Ge/Cu3Ge heterostructure show ambipolar transistor behavior with a large on/off current ratio of more than 105 and 103 for the hole and electron regimes at room temperature, respectively. Investigations of temperature‐dependent transport properties and low‐frequency current fluctuations reveal that the tunable effective Schottky barriers of the Ge NW transistors accounted for the ambipolar behaviors. It is further shown that this ambipolarity can be used to realize binary‐signal and data‐storage functions, which greatly simplify circuit design compared with conventional technologies.

Molecular Targeting‐Mediated Mild‐Temperature Photothermal Therapy with a Smart Albumin‐Based Nanodrug

By Ge Gao, Yao‐Wen Jiang, Wei Sun, Yuxin Guo, Hao‐Ran Jia, Xin‐Wang Yu, Guang‐Yu Pan, Fu‐Gen Wu from Wiley: Small: Table of Contents. Published on Aug 16, 2019.

A smart albumin‐based theranostic nanoagent composed of human serum albumin, dc‐IR825 (a cyanine dye and a photothermal agent), and gambogic acid (an HSP90 inhibitor and an effective anticancer drug) is fabricated, which can achieve the synergistic molecular targeting‐mediated mild‐temperature photothermal therapy and chemotherapy of cancer. Abstract Photothermal therapy (PTT) usually requires hyperthermia >50 °C for effective tumor ablation, which inevitably induces heating damage to the surrounding normal tissues/organs. Moreover, low tumor retention and high liver accumulation are the two main obstacles that significantly limit the efficacy and safety of many nanomedicines. To solve these problems, a smart albumin‐based tumor microenvironment‐responsive nanoagent is designed via the self‐assembly of human serum albumin (HSA), dc‐IR825 (a cyanine dye and a photothermal agent), and gambogic acid (GA, a heat shock protein 90 (HSP90) inhibitor and an anticancer agent) to realize molecular targeting‐mediated mild‐temperature PTT. The formed HSA/dc‐IR825/GA nanoparticles (NPs) can escape from mitochondria to the cytosol through mitochondrial disruption under near‐infrared (NIR) laser irradiation. Moreover, the GA molecules block the hyperthermia‐induced overexpression of HSP90, achieving the reduced thermoresistance of tumor cells and effective PTT at a mild temperature (

Ultraefficient Conversion of CO2 into Morphology‐Controlled Nanocarbons: A Sustainable Strategy toward Greenhouse Gas Utilization

By Chu Liang, Liangbin Pan, Sheng Liang, Yang Xia, Zhiqiang Liang, Yongping Gan, Hui Huang, Jun Zhang, Wenkui Zhang from Wiley: Small: Table of Contents. Published on Aug 16, 2019.

A variety of nanocarbons with different morphology and porosity are successfully synthesized by water introduction, ball milling, or heating LiH‐CO2 at the low temperatures. The reactant of LiH can be regenerated through a two closed‐loop reaction process including five‐stage reactions. This new strategy opens up a new avenue in tackling the long‐term challenges of greenhouse effect and environmental problems. Abstract The ability to efficiently convert CO2 into nanocarbons at low temperatures is highly desirable, as it would enable the environmentally benign utilization of greenhouse gases, yet this remains a considerable challenge. Herein, a one‐step, ultrafast, and scalable strategy is demonstrated to efficiently convert CO2 into morphology‐controlled nanocarbons at low temperatures. The conversion reactions between CO2 and LiH are achieved in less than 30 s at moderate conditions by introducing a very small amount of water, ball milling, or heating. Nanocarbons featuring wildly tunable morphology with characteristic dimensions ranging from nanoscale to macroscale are successfully synthesized by controlling the CO2 pressure and the synthesis routes. The gas blowing velocity and its distribution are revealed as the main reasons for the CO2 pressure and synthesis route dependent morphology and porosity of nanocarbons. Moreover, a two closed‐loop reaction process including five‐stage reactions is proposed for nanocarbons synthesis and LiH regeneration. The strategy provides a new opportunity for efficient and environmentally benign nanocarbons synthesis.

General Approach to Produce Nanostructured Binary Transition Metal Selenides as High‐Performance Sodium Ion Battery Anodes

By Zeeshan Ali, Muhammad Asif, Teng Zhang, Xiaoxiao Huang, Yanglong Hou from Wiley: Small: Table of Contents. Published on Aug 16, 2019.

A simplistic, scalable and general synthesis strategy is presented to employ various combinations of binary transition metal selenides (B‐TMSs) as anodes of sodium ion batteries. Synthesis of eight different B‐TMSs is presented while the process was optimized to obtain high surface area bearing and hierarchical nanosheets. Representative B‐TMSs present adequately high energy capacities, excellent rate capabilities and promising cycling stabilities. Abstract Multiple transition metals containing chalcogenides have recently drawn boosted attraction as anodes for sodium ion batteries (SIBs). Their greatly enhanced electrochemical performances can be attributed to the superior intrinsic conductivities and richer redox reactions, comparative to mono metal chalcogenides. To employ various binary metals comprising selenides (B‐TMSs) for SIBs, discovery of a simplistic, scalable and universal synthesis approach is highly desirable. Herein, a simple, facile, and comprehensive strategy to produce various combinations of nanostructured B‐TMSs is presented. As a proof of concept, optimized, high surface area bearing, and hierarchical nanosheets of iron–nickel selenide (FNSe), iron–cobalt selenide, and nickel–cobalt selenide are produced and employed in SIBs. These B‐TMSs exhibit adequately high energy capacities, excellent rate capabilities, and an extraordinarily stable life of 2600 cycles. As far as it is known, it is the first work to discuss sodium storage of FNSe, so various in situ and ex situ battery analyses are carried out to probe the sodium storage mechanism. When employed in sodium full batteries, these B‐TMSs present reasonably high reversible specific capacities even after 100 cycles. Overall, the presented strategy will pave the way for facile synthesis of numerous binary transition metal chalcogenides that are the potential materials for energy storage and conversion systems.

Interplay between Short‐ and Long‐Ranged Forces Leading to the Formation of Ag Nanoparticle Superlattice

By Jaewon Lee, Elias Nakouzi, Dongdong Xiao, Zhigang Wu, Miao Song, Colin Ophus, Jaehun Chun, Dongsheng Li from Wiley: Small: Table of Contents. Published on Aug 16, 2019.

The self‐assembly process of Ag nanoparticles is observed by in situ liquid transmission electron microscopy. The Ag nanoparticles self‐assembleinto a superlattice with short separation distance (

Elucidation of Photoluminescence Blinking Mechanism and Multiexciton Dynamics in Hybrid Organic–Inorganic Perovskite Quantum Dots

By Taehee Kim, Seok Il Jung, Sujin Ham, Heejae Chung, Dongho Kim from Wiley: Small: Table of Contents. Published on Aug 16, 2019.

Organic–inorganic hybrid perovskite quantum dots (PQDs) exhibit a size‐dependent trend in photoluminescence (PL) blinking and multiexciton dynamics. The mechanism of PL blinking in individual PQDs is revealed, and the effects of deep, shallow, and higher trap states are discriminated. The Auger recombination in smaller PQD is associated with efficient intraband transition and Auger ionization to the high‐energy trap states. Abstract Halide perovskites (ABX3) have emerged as promising materials in the past decade owing to their superior photophysical properties, rendering them potential candidates as solar cells, light‐emitting diode displays, and lasing materials. To optimize their utilization into optoelectronic devices, fundamental understanding of the optical behaviors is necessary. To reveal the comprehensive structure–property relationship, CH3NH3PbBr3 (MAPbBr3) perovskite quantum dots (PQDs) of three different sizes are prepared by controlling the precipitation temperature. Photoluminescence (PL) blinking, a key process that governs the emission efficiency of the PQD materials, is investigated in detail by the time‐resolved spectroscopic measurements of individual dots. The nature of the generated species in the course of blinking events is identified, and the mechanism governing the PL blinking is studied as a function of PQD sizes. Further, the practical applicability of MAPbBr3 PQDs is assessed by studying the multiexciton dynamics under high photoexcitation intensity under which most of the display devices work. Ultrafast transient absorption spectroscopy helped in uncovering the volume‐dependent Auger recombination rates, which are further explored by comparing the early‐time transitions related to surface trap states and higher band states.

A Gold Nanocage/Cluster Hybrid Structure for Whole‐Body Multispectral Optoacoustic Tomography Imaging, EGFR Inhibitor Delivery, and Photothermal Therapy

By Chenyue Zhan, Yong Huang, Guifang Lin, Shuailing Huang, Fang Zeng, Shuizhu Wu from Wiley: Small: Table of Contents. Published on Aug 16, 2019.

A hybrid gold cage‐based nanodrug has been developed for tumor inhibition via epidermal growth factor receptor pathway blockage and photothermal therapy, which can release the active drug in acidic tumor environment and achieve tumor ablation upon light irradiation. The release of the drug and biodistribution of the nanostructure can be, respectively, visualized by fluorescence imaging and multispectral optoacoustic tomography imaging. Abstract Gold nanocages (AuNCs) and gold nanoclusters (AuClusters) are two classes of advantageous nanostructures with special optical properties, and many other attractive properties. Integrating them into one nanosystem may achieve greater and smarter performance. Herein, a hybrid gold nanostructure for fluorescent and optoacoustic tomography imaging, controlled release of drugs, and photothermal therapy (PTT) is demonstrated. For this nanodrug (EA–AB), an epidermal growth factor receptor (EGFR) inhibitor erlotinib (EB) is loaded into AuNCs, which are then capped and functionalized by biocompatible AuCluster@BSA (BSA = bovine serum albumin) conjugates via electrostatic interaction. Upon cell internalization, the lysosomal proteases and low pH cause the release of EB from EA–AB, and also induce fluorescence restoration of the AuCluster for imaging. Irradiation with near‐infrared light further promotes the drug release and affords a PTT effect as well. The AuNC‐based nanodrug is optoacoustically active, and its biodistribution and metabolic process have been successfully monitored by whole‐body and 3D multispectral optoacoustic tomography imaging. Owing to the combined actions of PTT and EGFR pathway blockage, EA–AB exhibits marked tumor inhibition efficacy in vivo.

Masthead: (Small 33/2019)

By from Wiley: Small: Table of Contents. Published on Aug 16, 2019.

A Microfabricated Sandwiching Assay for Nanoliter and High‐Throughput Biomarker Screening

By Praveen Bandaru, Dafeng Chu, Wujin Sun, Soufian Lasli, Chuanzhen Zhao, Shuang Hou, Shiming Zhang, Jiahua Ni, Giorgia Cefaloni, Samad Ahadian, Mehmet Remzi Dokmeci, Shiladitya Sengupta, Junmin Lee, Ali Khademhosseini from Wiley: Small: Table of Contents. Published on Aug 16, 2019.

Polyprodrug Antimicrobials: Remarkable Membrane Damage and Concurrent Drug Release to Combat Antibiotic Resistance of Methicillin‐Resistant Staphylococcus aureus

By Bing Cao, Fengfeng Xiao, Da Xing, Xianglong Hu from Wiley: Small: Table of Contents. Published on Aug 16, 2019.

Pressure Sensors: Highly Uniform and Low Hysteresis Piezoresistive Pressure Sensors Based on Chemical Grafting of Polypyrrole on Elastomer Template with Uniform Pore Size (Small 33/2019)

By Jinwon Oh, Jin‐Oh Kim, Yunjoo Kim, Han Byul Choi, Jun Chang Yang, Serin Lee, Mikhail Pyatykh, Jung Kim, Joo Yong Sim, Steve Park from Wiley: Small: Table of Contents. Published on Aug 16, 2019.

In article number 1901744, Steve Park and co‐workers depict the fabrication of a highly uniform and low hysteresis porous pressure sensor. Using microfluidic emulsion, water droplets are generated and assembled in oil solution containing elastomer precursor. Upon annealing, a porous elastomer with uniform pore size is formed. The elastomer is then grafted with conductive polymer.

Direct Laser Writing: Additive Manufacturing of Nanostructures That Are Delicate, Complex, and Smaller than Ever (Small 33/2019)

By Andrew J. Gross, Katia Bertoldi from Wiley: Small: Table of Contents. Published on Aug 16, 2019.

In article number 1902370, Andrew J. Gross and Katia Bertoldi demonstrate two post‐processing techniques that use oxygen plasma etching to overcome fabrication limitations of two‐photon polymerization. These simple techniques allow for the fabrication of nanostructures with extreme geometry and reduced feature sizes, all while using commonly available materials and equipment.

Hydration‐Driven Superlattices: Interplay between Short‐ and Long‐Ranged Forces Leading to the Formation of Ag Nanoparticle Superlattice (Small 33/2019)

By Jaewon Lee, Elias Nakouzi, Dongdong Xiao, Zhigang Wu, Miao Song, Colin Ophus, Jaehun Chun, Dongsheng Li from Wiley: Small: Table of Contents. Published on Aug 16, 2019.

During the self‐assembly process, the dynamic behavior of nanoparticles is correlated with the van der Waals force over both short (≈2–3 nm) and relatively long particle separations (

Binary‐Metal Selenides: General Approach to Produce Nanostructured Binary Transition Metal Selenides as High‐Performance Sodium Ion Battery Anodes (Small 33/2019)

By Zeeshan Ali, Muhammad Asif, Teng Zhang, Xiaoxiao Huang, Yanglong Hou from Wiley: Small: Table of Contents. Published on Aug 16, 2019.

In article number 1901995, Yanglong Hou and co‐workers demonstrate a simplistic, scalable and general synthesis strategy employing various combinations of binary transition metal selenides (B‐TMSs) with high surface area and hierarchical nanosheet structures as promising anodes for sodium ion batteries (SIBs). Representative B‐TMSs anodes present adequately high energy capacities, excellent rate capabilities and extraordinary cycling stabilities.

Lithography: Two‐Photon Vertical‐Flow Lithography for Microtube Synthesis (Small 33/2019)

By Jonas Lölsberg, Arne Cinar, Daniel Felder, Georg Linz, Suzana Djeljadini, Matthias Wessling from Wiley: Small: Table of Contents. Published on Aug 16, 2019.

In article number 1901356, Matthias Wessling and co‐workers demonstrate a method for the continuous synthesis of three‐dimensional microtubes based on two‐photon polymerization. This approach provides rigorous control in generating thin‐walled microtubes with a tunable diameter and pore size.

Recent Development in Separators for High‐Temperature Lithium‐Ion Batteries

By Muhammad Waqas, Shamshad Ali, Chao Feng, Dongjiang Chen, Jiecai Han, Weidong He from Wiley: Small: Table of Contents. Published on Aug 16, 2019.

Separators are crucial for the safe operation of lithium ion batteries at high‐temperatures. This Review discusses the recent development in separator technologies for realizing high‐temperature lithium ion batteries by focusing on their layered structure design with various materials. Future challenges and directions are discussed for achieving remarkable performances of separators in a high‐temperature environment. Abstract Lithium‐ion batteries (LIBs) are promising energy storage devices for integrating renewable resources and high power applications, owing to their high energy density, light weight, high flexibility, slow self‐discharge rate, high rate charging capability, and long battery life. LIBs work efficiently at ambient temperatures, however, at high‐temperatures, they cause serious issues due to the thermal fluctuation inside batteries during operation. The separator is a key component of batteries and is crucial for the sustainability of LIBs at high‐temperatures. The high thermal stability with minimum thermal shrinkage and robust mechanical strength are the prime requirements along with high porosity, ionic conductivity, and electrolyte uptake for highly efficient high‐temperature LIBs. This Review deals with the recent studies and developments in separator technologies for high‐temperature LIBs with respect to their structural layered formation. The recent progress in monolayer and multilayer separators along with the developed preparation methodologies is discussed in detail. Future challenges and directions toward the advancement in separator technology are also discussed for achieving remarkable performance of separators in a high‐temperature environment.

Aggregation‐Induced Emission Gold Clustoluminogens for Enhanced Low‐Dose X‐ray‐Induced Photodynamic Therapy

By Wenjing Sun, Li Luo, Yushuo Feng, Yuting Cai, Yixi Zhuang, Rongjun Xie, Hongmin Chen, Xiaoyuan Chen from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 16, 2019.

Radiotherapy is highly effective against solid tumor with high doses of radiation. The use of gold nanoparticles as radiosensitizers is an effective way to boost the killing efficacy while drastically limiting the received dose and reducing the possible damage to normal tissues. Herein, we designed aggregation‐induced emission gold clustoluminogens (AIE‐Au) to achieve efficient low‐dose X‐ray‐induced photodynamic therapy with negligible side effects. The aggregations of glutathione‐protected gold clusters (GCs) assembled by cationic polymer enhanced X‐ray‐excited optical luminescence by 5.2‐fold. Under low‐dose X‐ray irradiation, AIE‐Au strongly absorbed X‐rays and efficiently generated hydroxyl radicals, which enhanced the radiotherapy effect. Additionally, AIE‐Au converted X‐rays to optical luminescence, which excited the conjugated photosensitizers, resulting in a photodynamic therapy effect. The in vitro and in vivo experiments demonstrated that AIE‐Au clustoluminogens effectively triggered the generation of reactive oxygen species with an order‐of‐magnitude reduction in the X‐ray dose, enabling highly effective cancer treatment via the unique X‐PDT mechanism.

Tue 19 Nov 14:00: Radio Protocol Vulnerabilities in 5G Networks

From All Talks (aka the CURE list). Published on Aug 16, 2019.

Radio Protocol Vulnerabilities in 5G Networks

Cellular devices support various technical features and services for 2G, 3G, 4G and upcoming 5G networks. For example, these technical features contain physical layer throughput categories, radio protocol information, security algorithm, carrier aggregation bands and type of services such as GSM -R, Voice over LTE etc. These technical features and network services termed as ‘device capabilities’ and exchanged with the network during the device registration and Authentication and Key Agreement (AKA) protocols. The 3rd Generation Partnership Project (3GPP) responsible for the worldwide standardization of cellular communication networks has designed and mandated the use of the AKA protocol to protect the subscribers’ mobile services.

In this talk, we discuss several vulnerabilities discovered in cellular device authentication and registration process in 5G networks. Low-cost hardware setup, proof-of-concepts attacks to demonstrate the impact, countermeasures, and remedial actions from 3GPP/GSMA for 5G networks will also be presented.

Add to your calendar or Include in your list

Enantioselective Dicarbofunctionalization of Unactivated Alkenes by Pd‐Catalyzed Tandem Heck/Suzuki‐Coupling Reaction

By Junliang Zhang, Zhan-Ming Zhang, Bing Xu, Lizhuo Wu, Yuanqi Wu, Yanyan Qian, Lujia Zhou, Yu Liu from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 16, 2019.

A highly enantioselective dicarbofunctionalization of unactivated alkenes was implemented by Pd‐catalyzed asymmetric tandem Heck/Suzuki‐coupling reaction. This represents the first example of highly enantioselective intramolecular cyclization/cross‐coupling of olefin‐tethered aryl halides with alkyl‐, alkenyl‐ or arylboronic acids, which provides a rapid access to a number of chiral compounds such as dihydrobenzofurans, indolines, chromanes and indanes bearing a quaternary stereocenter in good yields with excellent enantioselectivities. The practicality of this reaction was validated in the modification of biologically complex molecules such as peptides, piperitol, CB2 receptor agonists and so on. Moreover, the synthesis of two enantiomers can be easily realized by simple inversion of the coupling sequence.

The surface activity of the hydrated proton is substantially higher than that of hydroxide

By Sudipta Das, Bonn Mischa, Ellen Backus from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 16, 2019.

The behaviour of hydroxide and hydrated protons, the auto‐ionization products of water, at surfaces is important for a wide range of applications and disciplines. However, it is unknown at which bulk concentration these ions start to become surface active at the water‐air interface. Here, we report changes in the D2O‐air interface in the presence of excess D+hyd/OD‐hyd determined using surface‐sensitive vibrational Sum Frequency Generation spectroscopy. The onset of the perturbation of the D2O surface occurs at a bulk concentration as low as 2.7±0.2 mM D+hyd. In contrast, a concentration of several 100s mM OD‐hyd is required to change the D2O surface. The hydrated proton is thus orders of magnitude more surface‐active than hydroxide at the water‐air interface.

Simultaneous Quantification of the Interplay Between Molecular Turnover and Cell Mechanics by AFM–FRAP

By Mark Skamrahl, Huw Colin‐York, Liliana Barbieri, Marco Fritzsche from Wiley: Small: Table of Contents. Published on Aug 16, 2019.

Atomic force microscopy and fluorescence recovery after photobleaching (AFM–FRAP) are combined to simultaneously quantify mechanics and molecule kinetics in living cells. This optomechanical AFM–FRAP platform reveals adaptations of the actin turnover and filament lengths in stress fibers in response to a wide force application range at the apical cortex, highlighting a direct relationship of mechanosensation and the cellular actin cytoskeleton. Abstract Quantifying the adaptive mechanical behavior of living cells is essential for the understanding of their inner working and function. Yet, despite the establishment of quantitative methodologies correlating independent measurements of cell mechanics and its underlying molecular kinetics, explicit evidence and knowledge of the sensitivity of the feedback mechanisms of cells controlling their adaptive mechanics behavior remains elusive. Here, a combination of atomic force microscopy and fluorescence recovery after photobleaching is introduced offering simultaneous quantification and direct correlation of molecule kinetics and mechanics in living cells. Systematic application of this optomechanical atomic force microscopy–fluorescence recovery after photobleaching platform reveals changes in the actin turnover and filament lengths of ventral actin stress fibers in response to constant mechanical force at the apical actin cortex with a dynamic range from 0.1 to 10 nN, highlighting a direct relationship of active mechanosensation and adaptation of the cellular actin cytoskeleton. Simultaneous quantification of the relationship between molecule kinetics and cell mechanics may thus open‐up unprecedented insights into adaptive mechanobiological mechanisms of cells.

Multi‐component Synthesis of Rare 1,3‐Dihydro‐1,3‐azaborinine Derivatives ‐ Application of a Bora‐Nazarov Type Reaction

By Gerhard Erker, Jun Li, Constantin G Daniliuc, Christian Mück-Lichtenfeld, Gerald Kehr from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 16, 2019.

The twofold hydroboration products of (Fmes)BH2·SMe2 with a series of alkynes (2‐butyne, arylethynes) react with two molar equiv. of 2,6‐dimethylphenyl isocyanide (CN‐Xyl) at 80°C to give rare examples of 1,3‐azaborinine derivatives. A mechanistic study revealed a reaction course involving insertion of one isonitrile followed by a bora‐Nazarov type ring‐closure reaction and subsequent isonitrile insertion to give the respective 1,3‐dihydro‐1,3‐azaborinines 5.

An Unusual Skeletal Rearrangement in the Biosynthesis of the Sesquiterpene Trichobrasilenol from Trichoderma

By Keiichi Murai, Lukas Lauterbach, Kazuya Teramoto, Zhiyang Quan, Lena Barra, Tsuyoshi Yamamoto, Kenichi Nonaka, Kazuro Shiomi, Makoto Nishiyama, Tomohisa Kuzuyama, Jeroen Sidney Dickschat from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 16, 2019.

The skeletons of some classes of terpenoids are unusual, because they contain a larger number of Me groups (or their biosynthetic equivalents such as olefinic methylene groups, hydroxymethyl groups, aldehydes or carboxylic acids and their derivatives) than provided by their oligoprenyl diphosphate precursor. This is sometimes the result of an oxidative ring opening reaction at a terpene cyclase derived molecule containing the regular number of Me group equivalents, as observed for picrotoxan sesquiterpenes. In this study a sesquiterpene cyclase from Trichoderma is described that can convert farnesyl diphosphate (FPP) directly via a remarkable skeletal rearrangement into trichobrasilenol, a new brasilane sesquiterpene with one additional Me group equivalent compared to FPP. A mechanistic hypothesis for the formation of the brasilane skeleton is supported by extensive isotopic labelling studies.

A Camptothecin‐Grafted DNA Tetrahedron as a Precise Nanomedicine to Inhibit Tumor Growth

By Jiao Zhang, Yuanyuan Guo, Fei Ding, Gaifang Pan, Xinyuan Zhu, Chuan Zhang from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 16, 2019.

A general approach is developed to construct a precise drug‐containing DNA framework with defined drug content and architecture via drug conjugation on PS oligonucleotides and programmable DNA self‐assembly. With stimuli‐responsiveness and efficient cellular uptake, the DNA‐based drug delivery system exhibits enhanced antitumor efficacy both in vitro and in vivo. Abstract Most chemotherapeutics are hydrophobic molecules and need to be converted into hydrophilic form before administration. Based on the excellent hydrophilicity and programmability of DNA, now, a general strategy to construct a precise drug‐containing DNA framework for cancer treatment is reported. In this novel drug delivery system, carbonethyl bromide‐modified camptothecin (CPT) is employed to directly react with phosphorothioate (PS) modified DNAs, resulting in the formation of chemotherapeutics‐grafted DNAs with a responsive disulfide linkage. By tuning the number and site of PS modifications on DNA strands, hydrophilicity of the obtained DNA‐drug conjugates (DDCs) can be regulated to retain their aqueous solubility and capability of molecular recognition. Subsequently, programmable DNA nanotechnology enables the self‐assembly of a precise drug‐containing tetrahedral framework with stimuli‐responsive feature and enhanced antitumor efficacy both in vitro and in vivo.

Covalent Organic Frameworks as Favorable Constructs for Photodynamic Therapy

By Liang Zhang, Shibo Wang, Yi Zhou, Chao Wang, Xian‐Zheng Zhang, Hexiang Deng from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 16, 2019.

Covalent organic frameworks (COFs) with 2D π‐conjugation were designed and synthesized as molecular photosensitizers for efficient photodynamic therapy. Two molecules inactive to generating reactive oxygen species (ROS) were linked to form two COFs exhibiting excellent ROS production efficiency. The high permanent porosity of these COFs promoted both the diffusion of oxygen and the release of ROS in cells. Abstract Covalent organic frameworks (COFs) with 2D π‐conjugation were designed and synthesized as molecular photosensitizers for efficient photodynamic therapy. Two molecules, 5′,5′′′′‐(1,4‐phenylene)bis(([1,1′:3′,1′′‐terphenyl]‐4,4′′‐dicarbaldehyde)) (L‐3C) and 4,4′,4′′‐(1,4‐phenylene)bis(([2,2′:6′,2′′‐terpyridine]‐5,5′′‐dicarbaldehyde)) (L‐3N), inactive to generating reactive oxygen species (ROS), were linked to form two COFs, COF‐808 and COF‐909, respectively, exhibiting excellent ROS production efficiency. The high permanent porosity of these COFs (surface areas 2270 and 2610 m2 g−1) promoted diffusion of both oxygen and release of ROS in cells. This, combined with the excellent photostability and biocompatibility, led to excellent PDT performance. In vitro, over 80 % of tumor cells were killed after PDT treatment using COF‐909 at the concentration of 50 μg mL−1 for 150 s. In vivo, drastic reduction of tumor size was observed (from 9 mm to less than 1 mm) after 10 day treatment.

Bi2O3 Nanosheets Grown on Multi‐Channel Carbon Matrix to Catalyze Efficient CO2 Electroreduction to HCOOH

By Subiao Liu, Xue Feng Lu, Jing Xiao, Xin Wang, Xiong Wen (David) Lou from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 16, 2019.

Ultrathin Bi2O3 nanosheets have been successfully grown on a conductive multi‐channel carbon matrix (Bi2O3NSs@MCCM). The obtained Bi2O3NSs@MCCM electrocatalyst achieves a comparably high current density at a moderate overpotential for electrochemical CO2 reduction to HCOOH with high selectivity and good long‐term stability. Abstract Bi2O3 nanosheets were grown on a conductive multiple channel carbon matrix (MCCM) for CO2RR. The obtained electrocatalyst shows a desirable partial current density of ca. 17.7 mA cm−2 at a moderate overpotential, and it is highly selective towards HCOOH formation with Faradaic efficiency approaching 90 % in a wide potential window and its maximum value of 93.8 % at −1.256 V. It also exhibits a maximum energy efficiency of 55.3 % at an overpotential of 0.846 V and long‐term stability of 12 h with negligible degradation. The superior performance is attributed to the synergistic contribution of the interwoven MCCM and the hierarchical Bi2O3 nanosheets, where the MCCM provides an accelerated electron transfer, increased CO2 adsorption, and a high ratio of pyrrolic‐N and pyridinic‐N, while ultrathin Bi2O3 nanosheets offer abundant active sites, lowered contact resistance and work function as well as a shortened diffusion pathway for electrolyte.

Microstructural and Interfacial Designs of Oxygen‐Permeable Membranes for Oxygen Separation and Reaction–Separation Coupling

By Xuefeng Zhu, Weishen Yang from Wiley: Advanced Materials: Table of Contents. Published on Aug 16, 2019.

The oxygen permeability and stability of mixed ionic–electronic conducting membranes can be improved through microstructural and interfacial designs, while the optimized membranes are ready as membrane reactors for process intensification and new technology development. The new membrane reactors will trigger innovations in natural gas conversion, ammonia synthesis and hydrogen‐related clean energy technologies. Abstract Mixed ionic–electronic conducting oxygen‐permeable membranes can rapidly separate oxygen from air with 100% selectivity and low energy consumption. Combining reaction and separation in an oxygen‐permeable membrane reactor significantly simplifies the technological scheme and reduces the process energy consumption. Recently, materials design and mechanism investigations have provided insight into the microstructural and interfacial effects. The microstructures of the membrane surfaces and bulk are closely related to the interfacial oxygen exchange kinetics and bulk diffusion kinetics. Therefore, the permeability and stability of oxygen‐permeable membranes with a single‐phase structure and a dual‐phase structure can be adjusted through their microstructural and interfacial designs. Here, recent advances in the development of oxygen permeation models that provide a deep understanding of the microstructural and interfacial effects, and strategies to simultaneously improve the permeability and stability through microstructural and interfacial design are discussed in detail. Then, based on the developed high‐performance membranes, highly effective membrane reactors for process intensification and new technology developments are highlighted. The new membrane reactors will trigger innovations in natural gas conversion, ammonia synthesis, and hydrogen‐related clean energy technologies. Future opportunities and challenges in the development of oxygen‐permeable membranes for oxygen separation and reaction–separation coupling are also explored.

Two‐Sidedness of Surface Reaction Mediation

By Haoran Chen, Hao Zhu, Zhichao Huang, Wenhui Rong, Kai Wu from Wiley: Advanced Materials: Table of Contents. Published on Aug 16, 2019.

A surface reaction can be efficiently mediated by various strategies, which are explored from the perspectives of the surface and molecule manipulations as well as their interlinked effects. In addition to the reaction temperature, such two‐sidedness for the surface reaction mediation is related to the pre‐exponential factor and the energy barrier in the Arrhenius equation. Abstract A heterogeneous catalytic process involves many surface elementary steps that affect the overall catalytic performance in one way or another. In general, a high‐performance heterogeneous catalyst should meet the main criteria: excellent catalytic activity and high selectivity toward target products. Using surface science techniques, the two‐sidedness of the surface reaction mediations can be explored, from the perspectives of the surface and the molecule manipulations. The surface manipulation refers to a reaction that is mediated by composition and structure of the substrate as well as surface species, while the molecular manipulation relates to a reaction that is mediated by the reacting molecule via the precursor selection, environmental control, or external excitation. The best catalytic system should consist of the most efficient catalyst and the best suitable reacting molecule, in addition to its economic benefit and environmental amity. Recent research progress in surface reaction mediation is outlined, and its two‐sidedness is governed by the Arrhenius equation. This should shed new light on the connection between basic theory and surface reaction mediation strategies. To conclude, challenges and possible opportunities are elaborated for efficient surface reaction mediations.

Ultrastretchable and Wireless Bioelectronics Based on All‐Hydrogel Microfluidics

By Yaming Liu, Tiyun Yang, Yuyan Zhang, Gang Qu, Shanshan Wei, Zhou Liu, Tiantian Kong from Wiley: Advanced Materials: Table of Contents. Published on Aug 16, 2019.

Stretchable and wireless bioelectronics based on all‐hydrogel microfluidics and liquid metal are fabricated by combining a two‐step crosslinking mechanism and a laser‐engraving method. The perfused liquid metal in hydrogel microchannels form tailor‐designed conductive networks of hydrogel bioelectronics. The applications of all‐hydrogel‐based bioelectronics are demonstrated as wearable and potentially implantable sensors for monitoring physiologically relevant signals wirelessly. Abstract Hydrogel bioelectronics that can interface biological tissues and flexible electronics is at the core of the growing field of healthcare monitoring, smart drug systems, and wearable and implantable devices. Here, a simple strategy is demonstrated to prototype all‐hydrogel bioelectronics with embedded arbitrary conductive networks using tough hydrogels and liquid metal. Due to their excellent stretchability, the resultant all‐hydrogel bioelectronics exhibits stable electrochemical properties at large tensile stretch and various modes of deformation. The potential of fabricated all‐hydrogel bioelectronics is demonstrated as wearable strain sensors, cardiac patches, and near‐field communication (NFC) devices for monitoring various physiological conditions wirelessly. The presented simple platform paves the way of implantable hydrogel electronics for Internet‐of‐Things and tissue–machine interfacing applications.

Nb2O5/RGO Nanocomposite Modified Separators with Robust Polysulfide Traps and Catalytic Centers for Boosting Performance of Lithium–Sulfur Batteries

By Pengqian Guo, Kai Sun, Xiaonan Shang, Dequan Liu, Yanrong Wang, Qiming Liu, Yujun Fu, Deyan He from Wiley: Small: Table of Contents. Published on Aug 16, 2019.

Nb2O5 nanocrystals embedded into reduced graphene oxide nanosheets are designed as chemical anchors and conversion accelerators of lithium polysulfides (LiPSs) for high‐rate lithium–sulfur batteries (LSBs). The Nb2O5 nanocrystals can effectively catalyze the redox kinetics of long‐chain LiPSs to short‐chain Li2S2/Li2S. Abstract Lithium–sulfur batteries (LSBs) have shown great potential for application in high‐density energy storage systems. However, the performance of LSBs is hindered by the shuttle effect and sluggish reaction kinetics of lithium polysulfides (LiPSs). Herein, heterostructual Nb2O5 nanocrystals/reduced graphene oxide (Nb2O5/RGO) composites are introduced into LSBs through separator modification for boosting the electrochemical performance. The Nb2O5/RGO heterostructures are designed as chemical trappers and conversion accelerators of LiPSs. Originating from the strong chemical interactions between Nb2O5 and LiPSs as well as the superior catalytic nature of Nb2O5, the Nb2O5/RGO nanocomposite possesses high trapping efficiency and efficient electrocatalytic activity to long‐chain LiPSs. The effective regulation of LiPSs conversion enables the LSBs enhanced redox kinetics and suppressed shuttle effect. Moreover, the Nb2O5/RGO nanocomposite has abundant sulfophilic sites and defective interfaces, which are beneficial for the nucleation and growth of Li2S, as evidenced by analysis of the cycled separators. As a result, LSBs with the Nb2O5/RGO‐modified separators exhibit excellent rate capability (816 mAh g−1 at 3 A g−1) and cyclic performance (628 mAh g−1 after 500 cycles). Remarkably, high specific capacity and stable cycling performance are demonstrated even at an elevated temperature of 50 °C or with higher sulfur loadings.

Highly Enhanced Pseudocapacitive Performance of Vanadium‐Doped MXenes in Neutral Electrolytes

By Zhi‐Wen Gao, Weiran Zheng, Lawrence Yoon Suk Lee from Wiley: Small: Table of Contents. Published on Aug 16, 2019.

Vanadium‐doped titanium carbide (Ti3C2Tx MXene) nanosheets are prepared via a simple hydrothermal method to tune the interaction between MXene and alkali metal adsorbates (Li+, Na+, and K+) in neutral electrolytes. The strong alkali metal ion–O interaction on the V‐doped MXene surface boosts the capacitance to 404.9 F g−1, which is comparable to the performance under acidic conditions. Abstract 2D titanium carbide (Ti3C2Tx MXene) is recognized as a promising material for pseudocapacitor electrodes in acidic solutions, while the current studies in neutral electrolytes show much poorer performances. By a simple hydrothermal method, vanadium‐doped Ti3C2Tx 2D nanosheets are prepared to tune the interaction between MXene and alkali metal adsorbates (Li+, Na+, and K+) in the neutral electrolyte. Maintaining the 2D morphology of MXene, the coexisting V3+ and V4+ are confirmed to form surface V–C and V–O species. At a medium doping level of V:Ti = 0.17:1, the V‐doped MXene exhibits the highest capacitance of 365.9 F g−1 in 2 m KCl (10 mV s−1) and excellent stability (5% loss after 5000 cycles), compared to only 115.7 F g−1 of pristine MXene. Density functional theory calculations reveal the stronger alkali metal ion–O interaction on V‐doped MXene surface than unmodified MXene and a further capacitance boost to 404.9 F g−1 using Li+‐containing neutral electrolyte is reported, which is comparable to the performance under acidic conditions.

Synergic Catalysts of Polyoxometalate@Cationic Porous Aromatic Frameworks: Reciprocal Modulation of Both Capture and Conversion Materials

By Jian Song, Yue Li, Ping Cao, Xiaofei Jing, Muhammad Faheem, Yutaka Matsuo, Youliang Zhu, Yuyang Tian, Xiaohong Wang, Guangshan Zhu from Wiley: Advanced Materials: Table of Contents. Published on Aug 16, 2019.

A cationic porous aromatic framework is combined with catalytically active polyoxometalate anions for oxidative catalysis. The preferential substance‐capturing by the cationic framework enhances the catalytic activity of the active sites. In turn, anion incorporation creates hierarchical structures within the framework and promotes the mass transfer. The structural alteration and the synergistic effect of the compositional catalyst are discussed. Abstract Compositional catalysts based on porous supports and incorporated catalytic nanoparticles have achieved great successes during the past decades. However, rational design of synergic catalysts and modulating the interactions between functional supports and catalytic sites are still far from being well developed. In this work, aiming at overcoming the difficulties of comprehensive screening of porous supports and correspondingly matched catalytic sites, a cationic porous aromatic framework as a capturing platform and polyoxometalate anions as conversion materials are separately designed, and their combination is modularly controlled. The resulting composites show higher catalytic activities than the corresponding conversion sites themselves. Notably, the resulting composites uncommonly exhibit increased surface area and enlarged pore openings after the incorporation of nanoparticles, and lead to the promotion of mass transfer within the porous supports. The emergence of a hierarchical structure with increased surface area induced by guest loading is desired in heterogeneous catalysis. The reciprocal modulation of both capture and conversion materials results in enhanced conversion and increased reaction rate, indicating the successful preparation of synergic catalysts by this separate design approach.

Boosting the Reversibility of Sodium Metal Anode via Heteroatom‐Doped Hollow Carbon Fibers

By Xueying Zheng, Peng Li, Zhang Cao, Wei Luo, Fazhe Sun, Zhongqiang Wang, Bing Ding, Guoxiu Wang, Yunhui Huang from Wiley: Small: Table of Contents. Published on Aug 16, 2019.

Heteroatom‐doped hollow carbon fibers with uniform N, S doping and rich defects are synthesized to manipulate Na ion distribution at the electrolyte/electrode interface, which enables a stable Na metal anode with long cycle life and high efficiency. Its superiority is further extended to symmetric and full‐cells, demonstrating great promise in constructing a highly reversible Na metal anode. Abstract Sodium (Na) metal anodes stand out with their remarkable capacity and natural abundance. However, the dendritic Na growth, infinite dimensional changes, and low Coulombic efficiency (CE) present key bottlenecks plaguing practical applications. Here, heteroatom‐doped (nitrogen, sulfur) hollow carbon fibers (D‐HCF) are rationally synthesized as a nucleation‐assisting host to enable a highly reversible Na metal. The “sodiophilic” functional groups introduced by the heteroatom‐doping and large surface area (≈1052 m2 g−1) synchronously contribute to a homogenous plating morphology with dissipated local current density. High “sodiophilicity” of the D‐HCF is confirmed by first‐principle calculations and experimental results, where strong adsorption energy of −3.52 eV with low Na+ nucleation overpotential of 3.2 mV at 0.2 mA cm−2 is realized. As such, highly reversible plating/stripping is achieved at 1.0 mA cm−2 with average CE approximating 99.52% over 600 cycles. The as‐assembled Na@D‐HCF symmetric cells exhibit a prolonged lifetime for 1000 h. A full‐cell paired with Na3V2(PO4)3 cathode further demonstrates stable electrochemical behavior for 200 cycles at 1 C along with excellent rate performance (102 mAh g−1 at 5 C). The results clearly show the effectiveness of the D‐HCF in manipulating Na+ deposition and thus the significance of nucleation control in realizing dendrite‐free metal anodes.

Copper‐rich thermoelectric sulfides: size mismatch effect and chemical disorder in the [TS4]Cu6 complexes of Cu26T2Ge6S32 (T = Cr, Mo, W) colusites

By Ventrapati Pavan Kumar, Gabin Guélou, Pierric Lemoine, Bernard Raveau, Andrew Supka, Rabih Al Rahal Al Orabi, Marco Fornari, Koichiro Suekuni, Emmanuel Guilmeau from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 16, 2019.

In the present study, we investigate the Mo and W for Cr substitution in the synthetic mineral colusite, Cu26Cr2Ge6S32. Primarily, we elucidate the origin of extremely low electrical resistivity which does not compromise the Seebeck coefficient and leads to outstanding power factors of 1.94 mW m‐1 K‐2 at 700 K in Cu26Cr2Ge6S32. We demonstrate that the abnormally long iono‐covalent T‐S bonds competing with short metallic Cu‐T interactions govern the electronic transport properties of the conductive “Cu26S32” framework. Additionally, we address the key role of the cationic size‐mismatch at the core of the mixed tetrahedral‐octahedral complex, illustrated by the cation‐size variance, σ2, over the transport properties. Using a combination of experimental and theoretical tools, the explanation for the remarkable electrical and thermal transport properties of the Cu26Cr2‐xMoxGe6S32 and Cu26Cr2‐xWxGe6S32 solid solutions is discussed. In‐depth structural analysis using Rietveld refinements of XRPD data reveals two essential effects caused by the substitution of Cr in the solid solutions: (1) Only the tetrahedra that are directly bonded to the [TS4]Cu6 complex are significantly distorted upon substitution and (2) the major contribution to the disorder is localized at the central position of the mixed tetrahedral‐octahedral complex, and is maximized for x = 1, i.e. for the highest cationic size‐variance, σ2. We investigated the low‐ (5 ≤ T / K ≤ 300) and high‐ (300 ≤ T / K ≤ 700) temperature electrical and thermal transport properties, including electrical resistivity, Seebeck coefficient, thermal conductivity, and Hall effect (low temperature only) measurements and linked the structural/chemical disorder to the radically different conduction mechanisms in the Cu26Cr2‐xMoxGe6S32 and Cu26Cr2‐xWxGe6S32 solid solutions.

Amorphous Sn/Crystalline SnS2 Nanosheets via In Situ Electrochemical Reduction Methodology for Highly Efficient Ambient N2 Fixation

By Pengxiang Li, Wenzhi Fu, Peiyuan Zhuang, Yudong Cao, Can Tang, Angelica Blake Watson, Pei Dong, Jianfeng Shen, Mingxin Ye from Wiley: Small: Table of Contents. Published on Aug 16, 2019.

An amorphous Sn/crystalline SnS2 nanosheet is synthesized by an L‐cysteine‐based hydrothermal process followed by in situ electrochemical reduction, which shows excellent performance in the nitrogen reduced reaction with an ammonia production rate of 23.8 µg h−1 mg−1 at −0.8 V versus reversible hydrogen electrode (RHE) and Faradaic efficiency of 6.5% at −0.7 V versus RHE. Abstract Electrochemical nitrogen reduction reaction (NRR) as a new strategy for synthesizing ammonia has attracted ever‐growing attention, due to its renewability, flexibility, and sustainability. However, the lack of efficient electrocatalysts has hampered the development of such reactions. Herein, a series of amorphous Sn/crystalline SnS2 (Sn/SnS2) nanosheets by an L‐cysteine‐based hydrothermal process, followed by in situ electrochemical reduction, are synthesized. The amount of reduced amorphous Sn can be adjusted by selecting electrolytes with different pH values. The optimized Sn/SnS2 catalyst can achieve a high ammonia yield of 23.8 µg h−1 mg−1, outperforming most reported noble‐metal NRR electrocatalysts. According to the electrochemical tests, the conversion of SnS2 to an amorphous Sn phase leads to the substantial increase of its catalytic activity, while the amorphous Sn is identified as the active phase. These results provide a guideline for a rational design of low‐cost and highly active Sn‐based catalysts thus paving a wider path for NRR.

Self‐stabilized Amorphous Organic Room Temperature Phosphorescence

By Wei Xu, Yaguo Yu, Xiaonan Ji, Huarui Zhao, Jinming Chen, Yanyan Fu, Huimin Cao, Qingguo He, Jiangong Cheng from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 16, 2019.

The stability of pure organic room‐temperature phosphorescent (RTP) materials in air is one of the research hotspot in recent years. Without crystallization or encapsulation, a new strategy was proposed to obtain self‐stabilized organic RTP materials, based on a complete ionization of photo‐induced charge separation system. The ionization of aromatic phenol 4‐carbazolyl salicylaldehyde (CSA), formed a stable H‐bonding anion‐cation radical structure, and led to the completely amorphous CSA‐I film. Long phosphorescent lifetime was gained as long as 0.14 s at room temperature and a direct exposure in air. The emission intensity was also increased by 21.5 times. Such amorphous RTP material reconciled the contradiction between phosphorescence stability and vapor permeability, and has been successfully utilized for peroxide vapor detection.

Scale‐up Synthesis of Amorphous NiFeMo Oxides and Their Rapid Surface Reconstruction for Superior Oxygen Evolution Catalysis

By Shu-Hong Yu, Yu Duan, Zi-You Yu, Shao-jin Hu, Xu-Sheng Zheng, Chu-Tian Zhang, Hong-He Ding, Bi-Cheng Hu, Qi-Qi Fu, Zhi-Long Yu, Xiao Zheng, Jun-Fa Zhu, Min-Rui Gao from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 16, 2019.

Anode oxygen evolution reaction (OER) is known to largely limit the efficiency of electrolyzers owing to its sluggish kinetics. While crystalline metal oxides have demonstrated big potential as OER catalysts, their amorphous phases also show high activities. Synthetic efforts to produce amorphous metal oxides, however, have progressed slowly, and how amorphous structure benefits the catalytic performances remain elusive. We report here the first scalable synthesis of amorphous NiFeMo oxide (up to 515 grams one batch) with homogeneous elemental distribution via a facile supersaturated co‐precipitation method. In contrast to its crystalline counterpart, the amorphous NiFeMo oxide undergoes a faster surface self‐reconstruction process during OER, forming metal oxy(hydroxide) active layer with rich oxygen vacancies, which leads to superior OER activity with 280 mV overpotential at 10 mA cm‐2 in 0.1 M KOH. This work opens up the potential of fast, facile and scale‐up production of amorphous metal oxides for high‐performance OER catalysts.

Dianionic Mononuclear Cyclo‐P4 Complexes of Zero‐Valent Molybdenum: Coordination of the Cyclo‐P4 Dianion in the Absence of Intramolecular Charge Transfer

By Kyle A. Mandla, Michael L. Neville, Curtis E. Moore, Arnold L. Rheingold, Joshua S. Figueroa from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 16, 2019.

Relative to other cyclic poly‐phosphorus species (i.e. cyclo‐Pn), the planar cyclo‐P4 group is unique in its requirement of two additional electrons to achieve aromaticity. In the coordination chemistry of cyclo‐P4 ligands, these additional electrons are supplied from one or more metal centers. However the degree of charge transfer to the cyclo‐P4 ligand is highly dependent on the nature of the metal fragment to which it is bound. Reported here are unique examples of dianionic mononuclear η4‐P4 complexes that can be viewed as the simple coordination of the [cyclo‐P4]2– dianion to a neutral metal fragment. Treatment of the neutral, molybdenum cyclo‐P4­ complexes Mo(η4‐P4)I2(CO)(CNArDipp2)2 and Mo(η4‐P4)(CO)2(CNArDipp2)2 with KC8 produces the dianionic, three‐legged piano stool complexes, [Mo(η4‐P4)(CO)(CNArDipp2)2]2– and [Mo(η4‐P4)(CO)2(CNArDipp2)]2–, respectively. Structural, spectroscopic and computational studies on these dianions reveal a distinct similarity to the classic η6‐benzene complex (η6‐C6H6)Mo(CO)3 with respect to both the valence state of the metal center and electronic population of the π‐system of the planar‐cyclic ligand.

Copper‐Halide Polymer Nanowires as Versatile Supports for Single‐Atom Catalysts

By Min‐Seok Kim, Haedong Park, Sung Ok Won, Aditya Sharma, Jimin Kong, Hyun S. Park, Yun‐Mo Sung, Tae Joon Park, Myoung‐Woon Moon, Kahyun Hur from Wiley: Small: Table of Contents. Published on Aug 16, 2019.

Copper‐halide inorganic polymers self‐assemble to copper‐halide nanowires via hydrogen bonds. These nanowires with sub‐nanometer pores successfully anchor isolated atoms and apply to supports for single‐atom catalysts. Abstract Single‐atom catalysts are heterogeneous catalysts with atomistically dispersed atoms acting as a catalytically active center, and have recently attracted much attention owing to the minimal use of noble metals. However, a scalable and inexpensive support that can stably anchor isolated atoms remains a challenge due to high surface energy. Here, copper‐halide polymer nanowires with sub‐nanometer pores are proposed as a versatile support for single‐atom catalysts. The synthesis of the nanowires is straightforward and completed in a few minutes. Well‐defined sub‐nanometer pores and a large free volume of the nanowires are advantageous over any other support material. The nanowires can anchor various atomistically dispersed metal atoms into the sub‐nanometer pores up to ≈3 at% via a simple solution process, and this value is at least twice as big as previously reported data. The hydrogen evolution reaction activity of −18.0 A mgPt−1 at −0.2 V overpotential shows its potential for single‐atom catalysts support.

Two‐dimensional conjugated aromatic networks as high‐site‐density and single‐atom electrocatalysts towards oxygen reduction reaction

By Shaoxuan Yang, Yihuan Yu, Meiling Dou, Zhengping Zhang, Liming Dai, Feng Wang from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 16, 2019.

The controllable design of single‐atom electrocatalysts with high‐site‐density and enhanced mass/volume specific activity holds tremendous potential for clean energy devices involving the oxygen reduction reaction (ORR). Herein, two‐dimensional conjugated aromatic networks (CAN) with ultra‐thin conjugated layers (ca. 3.5 nm) and high single‐metal‐atom‐site density (mass content of 10.7 wt.%, and 0.73 metal atoms per nm2) are prepared via a facile pyrolysis‐free route involving a one‐step ball milling of the solid‐phase‐synthesized polyphthalocyanine. These materials display outstanding ORR mass activity of 47 mA mgcat.–1 represents 1.3‐ and 6.4‐fold enhancements compared with Pt and Pt/C in benchmark Pt/C, respectively. Moreover, the primary Zn−air batteries constructed with CAN as an air electrode demonstrate a mass/volume power density of 880 W gcat.–1/615 W cmcat.–3 and stable long‐term operation for 100 h. Our strategy offers a new way to design high‐performance electrocatalysts with atomic precision for use in other energy storage and conversion applications.

Tight Xenon Confinement in Crystalline Sandwich‐like Hydrogen Bonded‐Dimeric Capsule of Cyclic Peptides

By Juan R. Granja, Andrea Pizzi, Haxel Lionel Ozores, Martin Calvelo, Rebeca García-Fandiño, Manuel Amorin, Giancarlo Terraneo Terraneo, Nicola Demitri, Silvia Bracco, Angiolina Comotti, Piero Sozzani, Pierangelo Metrangolo, Charl Bezuidenhout from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 16, 2019.

A cyclic hexapeptide containing three pyridyl moieties connected to its backbone forms hydrogen‐bonded dimers, which encapsulate tightly a single xenon atom, like a pearl in its shell. Supramolecular capsules self‐assemble hierarchically forming a porous supramolecular architecture whose cavities are filled by small molecules and gases. The dimers imprint their shape and symmetry to the captured xenon, as demonstrated by 129Xe NMR, X‐Ray diffraction, and computational studies.

Observing the reversible single molecule electrochemistry of Alexa Fluor 647 dyes using total internal reflection fluorescence microscopy

By Sanjun Fan, James E.A. Webb, Ying Yang, Daniel J. Nieves, Vinicius R. Gonçales, Jason Tran, Geva Hilzenrat, Mohaddeseh Kahram, Richard D. Tilley, Katharina Gaus, John Justin Gooding from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 16, 2019.

The cyanine‐based fluorophore Alexa Fluor 647 is a widely used fluorescent probe for cell bioimaging and super‐resolution microscopy applications, with excellent fluorescence quantum yields and high brightness. Herein is reported the reversible switching of the fluorescence intensity of Alexa 647 conjugated to the protein bovine serum albumin (BSA) and adsorbed onto indium tin oxide (ITO) electrodes under electrochemical potential control at the level of single protein molecules. The modulation of the fluorescence as a function of potential was observed using total internal reflectance fluorescence (TIRF) microscopy. The fluorescence intensity of the Alexa 647 decreased, or reached background levels at reducing potentials, but returned to normal intensity levels at oxidizing potentials. Experimental results showed that these electrochemically induced changes in fluorescence were sensitive to pH despite that BSA‐Alexa 647 fluorescence without applied potential is insensitive to pH between values of 4‐10. The lower the pH value, the greater the number of fluorescent spots that were observed to lose their intensity, indicating the involvement of electron and proton transfer in the fluorescence switching mechanism. These results provide us with a new and effective fluorescent label to study single molecule electrochemistry as well as provide a new approach to achieve fluorescence switching for super resolution light microscopy.

Tetravinylallene

By Michael Sherburn, Cecile Elgindy, Jas Ward from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 16, 2019.

The first chemical synthesis of tetravinylallene (3,5‐divinylhepta‐1,3,4,6‐tetraene) is reported. The final, key step of the synthesis involves a palladium‐catalyzed, Negishi‐type cross‐coupling involving 1,5‐transposition of a penta‐2‐en‐4‐yn‐1‐ol methanesulfonate. The unprecedented fundamental hydrocarbon is sufficiently stable to be purified by flash chromatography. A similar synthetic pathway grants access to the first substituted tetravinylallenes, which provide insights into the influence of substitution upon stability and reactivity. Tetravinylallenes are shown to break new ground in swift structural complexity creation, with three novel sequences reported.

Thu 12 Sep 15:00: Context-Based Zero-Interaction Authentication

From All Talks (aka the CURE list). Published on Aug 16, 2019.

Context-Based Zero-Interaction Authentication

Abstract: For the past several years, enthusiastic and ambitious projections have been made for the rapid growth of the Internet-of-Things (IoT) ecosystem. Intel, for instance, has predicted that by next year (2020), the number of connected IoT devices will grow to around 200 billion worldwide, which is more than 20 devices for every person. Where are all these IoT devices? It turns out that over 70% of currently deployed IoT devices are in business, manufacturing, and healthcare sectors, and domestic and personal IoT devices seem to be concentrated only in the hands of enthusiastic early adopters, but not the general public. Increasing the adoption of these devices will require them to become easier to use.

One of the main hindrances to the adoption of IoT is the long-standing tension between security and usability. In particular, one of the paramount concerns that have continued to vex researchers is the question of how to quickly, securely, and effortlessly establish a common security key between a newly introduced device and an existing network and to subsequently manage the established connection securely. This is an extremely important problem because key establishment is one of the first configuration steps that needs to be done after powering a device on. And, because IoT devices often have simplistic user interfaces, it is often one of the clumsiest steps. The goal of this work is to make key configuration transparent.

Context-based pairing and authentication is a promising solution to this challenge. It exploits spatiotemporal randomness in the ambient environment (e.g., audio, luminosity, or received signal strength indicator), often called contextual information. Devices that use context-based security take advantage of the fact that the common contextual information is shared only by a limited group of closely located devices. In this talk, we will discuss ways that we can use context-based pairing to transparently commission a new IoT device: to set it up, all you have to do is plug it in. We will discuss the difficulties with zero-involvement context-based pairing work, including reliability, key randomness, and key reconciliation.

Bio: I’m an assistant professor of Computer Science at Loyola University Chicago. I work on hardware and software for cyber-physical systems. My goal is to make IoT systems more efficient, reliable, and secure. Previously, I was a grad student in Computer Engineering at Wisconsin in the Wisely lab.”

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Fri 17 Jan 13:00: Prof. Stephen Baker - Title TBC BRADFORD HILL SEMINAR

From All Talks (aka the CURE list). Published on Aug 16, 2019.

Prof. Stephen Baker - Title TBC

Stephen Baker is a Wellcome Trust/Royal Society funded molecular microbiologist based at the Oxford University Clinical Research Unit (OUCRU) in Ho Chi Minh City, Vietnam. He has been at OUCRU since November 2007 and is the head of the enteric infections research group. He holds an Oxford University research lecturer’s position, is a senior lecturer in emerging infectious at the London School of Hygiene and Tropical Medicine and an honorary member of faculty at the Wellcome Trust Sanger Institute. His group studies the microbiology, genetics, epidemiology and treatment of enteric infections caused by members of the Enterobacteriaceae.

Details of this seminar will be published shortly.

BRADFORD HILL SEMINAR

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Fri 08 Nov 13:00: Prof. Mette Kalager - Title TBC BRADFORD HILL SEMINAR

From All Talks (aka the CURE list). Published on Aug 16, 2019.

Prof. Mette Kalager - Title TBC

Mette Kalager is Professor at the Department of Health Management and Health Economics, Institute of Health and Society, Faculty of Medicine at the University of Oslo, Norway.

Details of this seminar will be published shortly.

BRADFORD HILL SEMINAR

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Thu 05 Dec 14:30: Halfway to Rota's basis conjecture

From All Talks (aka the CURE list). Published on Aug 16, 2019.

Halfway to Rota's basis conjecture

In 1989, Rota made the following conjecture. Given n bases B1, ..., Bn in an n-dimensional vector space V, one can always find n disjoint bases of V, each containing exactly one element from each Bi (we call such bases transversal bases). Rota’s basis conjecture remains open despite its apparent simplicity and the efforts of many researchers (for example, the conjecture was recently the subject of the collaborative “Polymath” project). In this talk, I will discuss how to find (0.5 – o(1))n disjoint transversal bases, improving the previously best known bound of n/log n. This is joint work with Bucic, Kwan, and Sudakov.

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[ASAP] Harmonizing the Electronic Structures of the Adsorbate and Catalysts for Efficient CO2 Reduction

By An Zhang†?, Yongxiang Liang†?, Huiping Li‡?, Xinyu Zhao†, Yuliang Chen†, Boyan Zhang†, Wenguang Zhu‡, and Jie Zeng*† from Nano Letters: Latest Articles (ACS Publications). Published on Aug 16, 2019.

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Nano Letters
DOI: 10.1021/acs.nanolett.9b02782

[ASAP] Hydrogel-Coated Microneedle Arrays for Minimally Invasive Sampling and Sensing of Specific Circulating Nucleic Acids from Skin Interstitial Fluid

By Dana Al Sulaiman†#, Jason Y. H. Chang‡#, Nitasha R. Bennett‡, Helena Topouzi†, Claire A. Higgins†, Darrell J. Irvine*‡§??¶, and Sylvain Ladame*† from ACS Nano: Latest Articles (ACS Publications). Published on Aug 16, 2019.

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ACS Nano
DOI: 10.1021/acsnano.9b04783

[ASAP] Modular Molecular Nanoplastics

By Angelica Niazov-Elkan†, XiaoMeng Sui*‡, Ifat Kaplan-Ashiri§, Linda J. W. Shimon§, Gregory Leitus§, Erez Cohen†, Haim Weissman†, H. Daniel Wagner*‡, and Boris Rybtchinski*† from ACS Nano: Latest Articles (ACS Publications). Published on Aug 16, 2019.

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ACS Nano
DOI: 10.1021/acsnano.9b03670

[ASAP] Age-Dependent Translocation of Gold Nanoparticles across the Air–Blood Barrier

By Akira Tsuda*†, Thomas C. Donaghey†, Nagarjun V. Konduru†, Georgios Pyrgiotakis†, Laura S. Van Winkle‡, Zhenyuan Zhang†, Patricia Edwards‡, Jessica-Miranda Bustamante‡, Joseph D. Brain†, and Phillip Demokritou† from ACS Nano: Latest Articles (ACS Publications). Published on Aug 16, 2019.

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ACS Nano
DOI: 10.1021/acsnano.9b03019

[ASAP] The Kinetics of Small Extracellular Vesicle Delivery Impacts Skin Tissue Regeneration

By Helena Henriques-Antunes†§#‡, Renato M. S. Cardoso†?‡, Alessandra Zonari†?, Joana Correia†?, Ermelindo C. Leal†?, Adria´n Jime´nez-Balsa†?, Miguel M. Lino†?, Ana Barradas†?, Ivana Kostic†?, Ce´lia Gomes#, Jeffrey M. Karp?, Euge´nia Carvalho†???, and Lino Ferreira*†# from ACS Nano: Latest Articles (ACS Publications). Published on Aug 16, 2019.

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ACS Nano
DOI: 10.1021/acsnano.9b00376

[ASAP] Enhanced Thermoelectric Performance of As-Grown Suspended Graphene Nanoribbons

By Qin-Yi Li*†?, Tianli Feng‡§, Wakana Okita#, Yohei Komori†, Hiroo Suzuki#, Toshiaki Kato*#?, Toshiro Kaneko#, Tatsuya Ikuta†?, Xiulin Ruan*§, and Koji Takahashi†? from ACS Nano: Latest Articles (ACS Publications). Published on Aug 16, 2019.

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ACS Nano
DOI: 10.1021/acsnano.9b03521

[ASAP] PbSe Quantum Dots Sensitized High-Mobility Bi2O2Se Nanosheets for High-Performance and Broadband Photodetection Beyond 2 µm

By Peng Luo†, Fuwei Zhuge*†, Fakun Wang†, Linyuan Lian‡, Kailang Liu†, Jianbing Zhang‡, and Tianyou Zhai*† from ACS Nano: Latest Articles (ACS Publications). Published on Aug 16, 2019.

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ACS Nano
DOI: 10.1021/acsnano.9b03124

[ASAP] Engineering Orthogonal Polypeptide GalNAc-Transferase and UDP-Sugar Pairs

By Junwon Choi†‡?, Lauren J. S. Wagner§?, Suzanne B. P. E. Timmermans†?, Stacy A. Malaker†, Benjamin Schumann†?, Melissa A. Gray†, Marjoke F. Debets†¶, Megumi Takashima??, Jase Gehring#?, and Carolyn R. Bertozzi*†? from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 16, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b04695

[ASAP] A Synthetic Model of Enzymatic [Fe4S4]–Alkyl Intermediates

By Mengshan Ye, Niklas B. Thompson, Alexandra C. Brown, and Daniel L. M. Suess* from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 16, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b06975

[ASAP] Dynamic Protonation Dramatically Affects the Membrane Permeability of Drug-like Molecules

By Zhi Yue, Chenghan Li, Gregory A. Voth, and Jessica M. J. Swanson*† from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 16, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b04387

[ASAP] Synthetic Entry to Polyfunctionalized Molecules through the [3+2]-Cycloaddition of Thiocarbonyl Ylides

By Franz-Lucas Haut†, Christoph Habiger†, Klaus Speck‡, Klaus Wurst§, Peter Mayer‡, Johannes Nepomuk Korber‡, Thomas Mu¨ller†, and Thomas Magauer*† from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 16, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b07729

[ASAP] Photovoltaic Blend Microstructure for High Efficiency Post-Fullerene Solar Cells. To Tilt or Not To Tilt?

By Gang Wang†¶, Steven M. Swick†¶, Micaela Matta†¶, Subhrangsu Mukherjee§, Joseph W. Strzalka?, Jenna Leigh Logsdon†, Simone Fabiano?, Wei Huang†, Thomas J. Aldrich†, Tony Yang†, Amod Timalsina†, Natalia Powers-Riggs†, Joaquin M. Alzola†, Ryan M. Young†, Dean M. DeLongchamp*§, Michael R. Wasielewski*†‡, Kevin L. Kohlstedt*†, George C. Schatz*†, Ferdinand S. Melkonyan*†, Antonio Facchetti*†#, and Tobin J. Marks*† from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 16, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b03770

Targeted imaging and targeted therapy of breast cancer cells via fluorescence double template-imprinted polymer coated silicon nanoparticles by epitope approach

By Yukui Zhang from RSC - Nanoscale latest articles. Published on Aug 16, 2019.

Nanoscale, 2019, Accepted Manuscript
DOI: 10.1039/C9NR04655K, Paper
Hai-Yan Wang, Pei-Pei Cao, Zheng-Ying He, Xi-Wen He, Wen-You Li, Yu-Hao Li, Yukui Zhang
Targeting is vital for precise positioning and efficient therapy, and the integrated platform for diagnosis and therapy has attracted more and more attention. Herein, we established the dual-template molecularly imprinted...
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Tailoring Fluorescence Emissions, Quantum Yields, and White Light Emitting from Nitrogen-doped Graphene and Carbon Nitride Quantum Dots

By Jeng-Kuei Chang from RSC - Nanoscale latest articles. Published on Aug 16, 2019.

Nanoscale, 2019, Accepted Manuscript
DOI: 10.1039/C9NR05422G, Paper
Siyong Gu, Chien-Te Hsieh, Yasser Ashraf Gandomi, Jianlin Li, Xing Xing Yue, Jeng-Kuei Chang
Highly fluorescent N-doped graphene quantum dots (NGQDs) and graphitic carbon nitride quantum dots (CNQDs, g-C3N4) were synthesized using a solid-phase microwave-assisted (SPMA) technique. The SPMA method, based on the pyrolysis...
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Accelerated site-selective photooxidation on Au nanoparticles via electrochemically-assisted plasmonic hole ejection

By Tetsu Tatsuma from RSC - Nanoscale latest articles. Published on Aug 16, 2019.

Nanoscale, 2019, Accepted Manuscript
DOI: 10.1039/C9NR05988A, Paper
Hiroyasu NISHI, Tetsu Tatsuma
In order to induce electrochemical reactions by localized surface plasmon resonance (LSPR), semiconductors have been employed as electron or hole acceptors for plasmon-induced charge separation (PICS) in most cases. Here...
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Interfacial THz Generation From Graphene/Si Mixed-dimensional Van Der Waals Heterostructure

By Xin Long Xu from RSC - Nanoscale latest articles. Published on Aug 16, 2019.

Nanoscale, 2019, Accepted Manuscript
DOI: 10.1039/C9NR03570B, Paper
Zehan Yao, Yuanyuan Huang, Lipeng Zhu, Petr Obraztsov, Wanyi Du, Longhui Zhang, Xin Long Xu
Even though Si is the cost efficient and extensively existed semiconductor in modern optoelectronics, it is not considered as an effective THz emitter due to the low carrier drift velocity...
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Intermetallic Pd3Pb ultrathin nanoplate-constructed flowers with low-coordinated edge sites boost oxygen reduction performance

By Deren Yang from RSC - Nanoscale latest articles. Published on Aug 16, 2019.

Nanoscale, 2019, Accepted Manuscript
DOI: 10.1039/C9NR04021H, Paper
Sai Luo, Yang Ou, Lei Li, Junjie Li, Xingqiao Wu, Yi Jiang, Mingxi Gao, Xiaofang Yang, Hui Zhang, Deren Yang
Although tremendous efforts have been devoted in exploring non-Pt based electrocatalysts toward oxygen reduction reaction (ORR), the achievements in both catalytic activity and durability are still far from satisfactory. Here...
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Facile in Situ Synthesis of Ultrasmall Near-Infrared-Emitting Gold Glyconanoparticles with Enhanced Cellular Uptake and Tumor Targeting

By Zhili Rong from RSC - Nanoscale latest articles. Published on Aug 16, 2019.

Nanoscale, 2019, Accepted Manuscript
DOI: 10.1039/C9NR03821C, Paper
Jinbin Liu, Yaping Wang, Shufeng Ma, Zhiyi Dai, Zhili Rong
Simultaneously possessing high tumor-targeting efficiency, long blood circulation and low normal-tissue retention is critical to future clinically translatable nanomedicines. Herein, we report a facile in situ glycoconjugation strategy on the...
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Spin controlled wavefront shaping metasurface with low dispersion in visible frequencies

By Zhaowei Liu from RSC - Nanoscale latest articles. Published on Aug 16, 2019.

Nanoscale, 2019, Accepted Manuscript
DOI: 10.1039/C9NR03566D, Paper
Junxiao Zhou, Haoliang Qian, Hailu Luo, Shuangchun Wen, Zhaowei Liu
Similar to amplitude and phase, optical spin plays an important and nontrivial role in optics, which have been widely demonstrated in wavefront engineering, creation of new optical components, and sensitive...
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Pressure-induced structural transition and band gap evolution of double perovskite Cs2AgBiBr6 nanocrystals

By Bo Zou from RSC - Nanoscale latest articles. Published on Aug 16, 2019.

Nanoscale, 2019, Accepted Manuscript
DOI: 10.1039/C9NR07030C, Paper
Ruijing Fu, Yaping Chen, Xue Yong, Zhiwei Ma, Lingrui Wang, Pengfei Lv, Siyu Lu, Guanjun Xiao, Bo Zou
Lead-free double halide perovskite nanocrystals (NCs) are becoming attractive due to their non-toxic and exceptional stability as substitute material for lead-based perovskites. Herein, we investigated the relation between the structure...
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Trimetallic Palladium-Copper-Cobalt Alloyed Wavy Nanowires Advance Ethanol Electrooxidation in Alkaline Medium

By Zhi-You Zhou from RSC - Nanoscale latest articles. Published on Aug 16, 2019.

Nanoscale, 2019, Accepted Manuscript
DOI: 10.1039/C9NR05120A, Paper
Xun Wang, Fengling Zhao, Chaozhong Li, Qiang Yuan, Fang Yang, Bin Luo, Zixuan Xie, Xiaotong Yang, Zhi-You Zhou
Recently, engineering high performance Pd-based nanocatalysts for alkaline ethanol fuel cells has been paid wide attention. Here, we report a one-pot synthesis of low-palladium ternary palladium-copper-cobalt (PdCuCo) alloy nanowires (NWs)...
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An Electrochemical Gelation Method for Patterning Conductive PEDOT:PSS Hydrogels

By Vivian Rachel Feig, Helen Tran, Minah Lee, Kathy Liu, Zhuojun Huang, Levent Beker, David G. Mackanic, Zhenan Bao from Wiley: Advanced Materials: Table of Contents. Published on Aug 15, 2019.

PEDOT:PSS hydrogels are an important framework for creating conductive porous materials that are of broad interest to researchers in the fields of bioelectronics, tissue engineering, stretchable electronics, and energy. To incorporate these materials into devices, a novel patterning method is presented that uses electrochemically produced ions to rapidly generate PEDOT:PSS hydrogel patterns with high spatial resolution. Abstract Due to their high water content and macroscopic connectivity, hydrogels made from the conducting polymer PEDOT:PSS are a promising platform from which to fabricate a wide range of porous conductive materials that are increasingly of interest in applications as varied as bioelectronics, regenerative medicine, and energy storage. Despite the promising properties of PEDOT:PSS‐based porous materials, the ability to pattern PEDOT:PSS hydrogels is still required to enable their integration with multifunctional and multichannel electronic devices. In this work, a novel electrochemical gelation (“electrogelation”) method is presented for rapidly patterning PEDOT:PSS hydrogels on any conductive template, including curved and 3D surfaces. High spatial resolution is achieved through use of a sacrificial metal layer to generate the hydrogel pattern, thereby enabling high‐performance conducting hydrogels and aerogels with desirable material properties to be introduced into increasingly complex device architectures.

Surfactant‐Stripped Micelles for NIR‐II Photoacoustic Imaging through 12 cm of Breast Tissue and Whole Human Breasts

By Upendra Chitgupi, Nikhila Nyayapathi, Jeesu Kim, Depeng Wang, Boyang Sun, Changning Li, Kevin Carter, Wei‐Chiao Huang, Chulhong Kim, Jun Xia, Jonathan F. Lovell from Wiley: Advanced Materials: Table of Contents. Published on Aug 15, 2019.

A commercially available NIR‐II dye is encapsulated in Pluronic micelles and subjected to surfactant stripping. This results in the concentrated dye giving rise to absorption at 1064 nm. Photoacoustic imaging with a 1064 nm laser images the micelles though 12 cm of chicken breast tissue, a variety of preclinical animals models, and through whole human breasts of healthy adult female human volunteers. Abstract Surfactant‐stripped micelles are formed from a commercially available cyanine fluoroalkylphosphate (CyFaP) salt dye and used for high contrast photoacoustic imaging (PAI) in the second near‐infrared window (NIR‐II). The co‐loading of Coenzyme Q10 into surfactant‐stripped CyFaP (ss‐CyFaP) micelles improves yield, storage stability, and results in a peak absorption wavelength in the NIR‐II window close to the 1064 nm output of Nd‐YAG lasers used for PAI. Aqueous ss‐CyFaP dispersions exhibit intense NIR‐II optical absorption, calculated to be greater than 500 at 1064 nm. ss‐CyFaP is detected through 12 cm of chicken breast tissue with PAI. In preclinical animal models, ss‐CyFaP is visualized in draining lymph nodes of rats through 3.1 cm of overlaid chicken breast tissue. Following intravenous administration, ss‐CyFaP accumulates in neoplastic tissues of mice and rats bearing orthotopic mammary tumors without observation of acute toxic side effects. ss‐CyFaP is imaged through whole compressed human breasts in three female volunteers at depths of 2.6–5.1 cm. Taken together, these data show that ss‐CyFaP is an accessible contrast agent for deep tissue PAI in the NIR‐II window.

Access to Aryl‐Naphthaquinone Atropisomers via Phosphine‐Catalyzed Atroposelective (4+2) Annulations of δ‐Acetoxy Allenoates with 2‐Hydroxyquinone Derivatives

By Xin Chen, Dingding Gao, Dong Wang, Tong Xu, Wei Liu, Ping Tian, Xiaofeng Tong from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 15, 2019.

Although asymmetric phosphine catalysis is a powerful tool for the construction of various chiral carbon centers, its synthetic potential toward enantioenriched atropisomer has not been explored yet. Herein, we report a phosphine‐catalyzed highly atroposelective (4+2) annulation of δ‐acetoxy allenoate and 2‐hydroxyquinone derivative, which provides expedient access to aryl‐naphthaquinone atropisomers via the de novo construction of benzene ring. The two functions of catalyst, tertiary phosphine (Lewis base) and tertiary amine (Brønsted base), cooperatively enable this process with high regio‐ and enantio‐selectivity.

Exceeding Metal Capacity in Sandwich Complexes: Ligand‐unsupported Docking of Extra Metal Moieties at Edges of a Metal Sheet Sandwich Complex

By Tomoko Ishikawa, Akino Kawamura, Tsuyoshi Sugawa, Risako Moridaira, Koji Yamamoto, Tetsuro Murahashi from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 15, 2019.

The ligand‐unsupported accommodation of extra metal moieties in a sandwich complex is reported. Although it has been considered that the metal‐capacity of a metal sheet sandwich complex is strictly limited by the size of cyclic unsaturated hydrocarbon ligands, we found that the M‐M edge bonds in a metal sheet sandwich complex provide a ligand‐unsupported docking site for extra metal moieties, allowing expansion of metal‐capacity in sandwich complexes. The metal sheet sandwich complex [Pd₄(µ₄‐C₈H₈)(µ₄‐C₉H₉)]+, in which the ligand‐based metal‐capacity is full in terms of the usage of all C=C moieties of the smaller carbocyclic ligand C₈H₈ in coordination, can accommodate extra M⁰{P(OPh)₃}₂ (M = Pd, Pt) moieties without coordinative assistance by neither the C₉H₉ nor the C₈H₈ ligand.

High Precision Size Recognition and Separation in Synthetic 1D Nanochannels

By Donglin Jiang, Ping Wang, Qiuhong Jiang, Xinyi Chen, Matthew Addicoat, Ning Huang, Sasanka Dalapati, Thomas Heine, Fengwei Huo from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 15, 2019.

Covalent organic frameworks (COFs) allow elaborate manufacture of ordered one‐dimensional channels in the crystal. While this makes designing by topology diagram particularly attractive as a tool for assembling straight pores to facilitate mass transport, molecular recognition has been so far inaccessible. We define a superlattice of COFs, by engineering channels with persistent triangular shape and discrete pore size. We observe a size recognition regime that is different from the characteristic adsorption of COFs, where pore window and walls are cooperative so that triangular apertures sort molecules of one‐atom difference and notch nanogrooves confine them into single‐file molecular chains. The recognition and confinement are accurately described by sensitive spectroscopy and femto‐second dynamic simulations. The resulting COFs enable instantaneous separation of mixture to achieve infinite selectivity and 100% purity at ambient temperature and pressure. Our findings offer an approach to merge precise recognition, selective transport, and instantaneous separation in synthetic 1D channels.

Wed 28 Aug 14:00: Synthesis and applications of mechanically chiral molecules

From Materials Chemistry Research Interest Group. Published on Aug 15, 2019.

Synthesis and applications of mechanically chiral molecules

Abstract not available

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Wed 28 Aug 14:00: Synthesis and applications of mechanically chiral molecules

From All Talks (aka the CURE list). Published on Aug 15, 2019.

Synthesis and applications of mechanically chiral molecules

Abstract not available

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Reversible Formation of a Light‐responsive Catalyst by Utilizing Intermolecular Cooperative Effects

By Chloe Z.-J. Ren, Pablo Solís Muñana, Julien Dupont, Silvia Siru Zhou, Jack Li-Yang Chen from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 15, 2019.

A photo‐responsive system where structure formation is coupled to catalytic activity is presented. The observed catalytic activity is reliant on intermolecular cooperative effects that are present when amphiphiles assemble into vesicular structures. Photo‐responsive units within the amphiphilic pre‐catalysts allow for switching between assembled and disassembled states, thereby modulating the catalytic activity. The ability to reversibly form cooperative catalysts within a dynamic self‐assembled system represents a conceptually new tool for the design of complex artificial systems in water.

Development of Blood‐Cell‐Selective Fluorescent Biodots for Lysis‐Free Leukocyte Imaging and Differential Counting in Whole Blood

By Xin Ting Zheng, Yen Nee Tan from Wiley: Small: Table of Contents. Published on Aug 15, 2019.

Blood‐cell‐selective fluorescent biodots are derived from the systematic investigation of amino acid and polymer precursors for highly efficient leukocyte (white blood cell) labeling, imaging, and differential counting in whole blood, toward faster disease diagnosis in one test. Abstract Complete blood count with leukocyte (white blood cell, WBC) differential is one of the most frequently ordered clinical test for disease diagnosis. Herein, multifunctional fluorescent carbon dots derived from biomolecules (biodots) for rapid lysis‐free whole blood analysis are developed. Specifically, two types of biodots are molecularly engineered through hydrothermal synthesis for differential blood cells labeling. Type I biodots synthesized from amino acid (serine/threonine) precursors and passivated with polyethylenimine can label both red blood cells (RBCs) and WBCs with excellent contrast in fluorescence intensity, enabling direct counting of leukocytes in whole blood samples without a tedious RBC lysis step. It also allows three‐part leukocyte differential counting by flow cytometry without using expensive fluorophore‐conjugated antibodies. On the other hand, Type II biodots synthesized from the same amino acid precursors but passivated with a biopolymer (chitosan) are able to selectively lyse RBCs with greater than 98% efficiency to allow simultaneous fluorescent labeling of leukocytes for WBC counting in whole blood. It is envisioned that these novel nanoreagents, which eliminate the cumbersome lysis and antibody conjugation steps for selective labeling of different blood cells, would revolutionize disease diagnostics toward achieving faster, cheaper, and more accurate whole blood analyses in one test.

Signal Output of Triboelectric Nanogenerator at Oil–Water–Solid Multiphase Interfaces and its Application for Dual‐Signal Chemical Sensing

By Peng Jiang, Lei Zhang, Hengyu Guo, Chaoyu Chen, Changsheng Wu, Steven Zhang, Zhong Lin Wang from Wiley: Advanced Materials: Table of Contents. Published on Aug 15, 2019.

A single‐electrode liquid–solid contact triboelectric nanogenerator (TENG) is fabricated to investigate its signal output at oil–water–solid multiphase interfaces. Two distinctive signals are obtained when the TENG is inserted into the oil/water multiphase. Based on this, the first self‐powered dual‐signal detection of dopamine using a TENG is demonstrated. Abstract A liquid–solid contact triboelectric nanogenerator (TENG) based on poly(tetrafluoroethylene) (PTFE) film, a copper electrode, and a glass substrate for harvesting energy in oil/water multiphases is reported. There are two distinctive signals being generated, one is from the contact electrification and electrostatic induction between the liquid (water/oil) and the PTFE film (VTENG and ITENG); and the other is from the electrostatic induction in the copper electrode by the oil/water interfacial charges (ΔVinterface and Iinterface), which is generated only when the liquid–solid contact TENG is inserted across the oil/water interface. The two signals show interesting opposite changing trends that the VTENG and ITENG decrease while the oil/water interfacial signals of ΔVinterface and Iinterface increase after coating a layer of polydopamine on the surfaces of PTFE and glass via self‐polymerization. As an application of the observed phenomena, both the values of ITENG and Iinterface have a good linear relationship versus the natural logarithm of the concentration of the dopamine. Based on this, the first self‐powered dual‐signal detection of dopamine using TENG is demonstrated.

Adaptable and Reprogrammable Surfaces

By Anja S. Goldmann, Nathan R. B. Boase, Lukas Michalek, James P. Blinco, Alexander Welle, Christopher Barner‐Kowollik from Wiley: Advanced Materials: Table of Contents. Published on Aug 15, 2019.

Spatial and temporal control over the physical and chemical properties of surfaces and interfaces is a key challenge in contemporary materials science. A critical survey of the state‐of‐the‐art is presented, identifying key challenges and future directions in existing synthetic and characterization methods. Abstract Establishing control over chemical reactions on interfaces is a key challenge in contemporary surface and materials science, in particular when introducing well‐defined functionalities in a reversible fashion. Reprogrammable, adaptable and functional interfaces require sophisticated chemistries to precisely equip them with specific functionalities having tailored properties. In the last decade, reversible chemistries—both covalent and noncovalent—have paved the way to precision functionalize 2 or 3D structures that provide both spatial and temporal control. A critical literature assessment reveals that methodologies for writing and erasing substrates exist, yet are still far from reaching their full potential. It is thus critical to assess the current status and to identify avenues to overcome the existing limitations. Herein, the current state‐of‐the‐art in the field of reversible chemistry on surfaces is surveyed, while concomitantly identifying the challenges—not only synthetic but also in current surface characterization methods. The potential within reversible chemistry on surfaces to function as true writeable memories devices is identified, and the latest developments in readout technologies are discussed. Finally, we explore how spatial and temporal control over reversible, light‐induced chemistries has the potential to drive the future of functional interface design, especially when combined with powerful laser lithographic applications.

Thu 05 Dec 11:00: Power analysis

From All Talks (aka the CURE list). Published on Aug 15, 2019.

Thu 21 Nov 11:00: Repeated Measures and Mixed Model ANOVA

From All Talks (aka the CURE list). Published on Aug 15, 2019.

Thu 07 Nov 11:00: Categorical Data Analysis

From All Talks (aka the CURE list). Published on Aug 15, 2019.

Thu 17 Oct 11:00: Simple and multiple linear regression

From All Talks (aka the CURE list). Published on Aug 15, 2019.

Thu 10 Oct 11:00: Exploratory Data Analysis

From All Talks (aka the CURE list). Published on Aug 15, 2019.

[ASAP] Artificial Photosynthesis with Electron Acceptor/Photosensitizer-Aptamer Conjugates

By Guo-Feng Luo†, Yonatan Biniuri†, Wei-Hai Chen†, Ehud Neumann‡, Michael Fadeev†, Henri-Baptiste Marjault‡, Anjan Bedi†, Ori Gidron†, Rachel Nechushtai‡, David Stone†, Thomas Happe§, and Itamar Willner*† from Nano Letters: Latest Articles (ACS Publications). Published on Aug 15, 2019.

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Nano Letters
DOI: 10.1021/acs.nanolett.9b02880

[ASAP] Silicon Metasurfaces for Third Harmonic Geometric Phase Manipulation and Multiplexed Holography

By Bernhard Reineke†, Basudeb Sain†, Ruizhe Zhao‡, Luca Carletti§, Bingyi Liu?, Lingling Huang‡, Costantino De Angelis?, and Thomas Zentgraf*† from Nano Letters: Latest Articles (ACS Publications). Published on Aug 15, 2019.

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Nano Letters
DOI: 10.1021/acs.nanolett.9b02844

[ASAP] Opportunities and Challenges in DNA-Hybrid Nanomaterials

By Simone I. S. Hendrikse†, Sally L. Gras‡§, and Amanda V. Ellis*† from ACS Nano: Latest Articles (ACS Publications). Published on Aug 15, 2019.

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ACS Nano
DOI: 10.1021/acsnano.9b06186

[ASAP] Manipulation of Confined Polyelectrolyte Conformations through Dielectric Mismatch

By Trung Dac Nguyen† and Monica Olvera de la Cruz*‡† from ACS Nano: Latest Articles (ACS Publications). Published on Aug 15, 2019.

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ACS Nano
DOI: 10.1021/acsnano.9b03900

[ASAP] Correction to Spatially Resolved Chemical Detection with a Nanoneedle-Probe-Supported Biological Nanopore

By Kan Shoji, Ryuji Kawano, and Ryan J. White* from ACS Nano: Latest Articles (ACS Publications). Published on Aug 15, 2019.

ACS Nano
DOI: 10.1021/acsnano.9b06200

[ASAP] Renal-Clearable Porphyrinic Metal–Organic Framework Nanodots for Enhanced Photodynamic Therapy

By Huan Wang†‡#, Dongqin Yu†‡#, Jiao Fang§, Changcui Cao§, Zhen Liu*?, Jinsong Ren*†, and Xiaogang Qu*† from ACS Nano: Latest Articles (ACS Publications). Published on Aug 15, 2019.

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ACS Nano
DOI: 10.1021/acsnano.9b03531

[ASAP] A 4 V Class Potassium Metal Battery with Extremely Low Overpotential

By Minghui Ye, Jang-Yeon Hwang, and Yang-Kook Sun* from ACS Nano: Latest Articles (ACS Publications). Published on Aug 15, 2019.

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ACS Nano
DOI: 10.1021/acsnano.9b03915

[ASAP] Three-Dimensional Tetrathiafulvalene-Based Covalent Organic Frameworks for Tunable Electrical Conductivity

By Hui Li†, Jianhong Chang†, Shanshan Li†, Xinyu Guan†, Daohao Li†, Cuiyan Li†, Lingxue Tang†, Ming Xue†, Yushan Yan‡, Valentin Valtchev†?, Shilun Qiu†, and Qianrong Fang*† from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 15, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b06908

[ASAP] Nitrogen Bridged Diazocines: Photochromes Switching within the Near-Infrared Region with High Quantum Yields in Organic Solvents and in Water

By Pascal Lentes†, Eduard Stadler‡, Fynn Ro¨hricht†, Arne Brahms†, Jens Gro¨bner†, Frank D. So¨nnichsen†, Georg Gescheidt‡, and Rainer Herges*† from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 15, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b06104

[ASAP] Localized Electronic Structure of Nitrogenase FeMoco Revealed by Selenium K-Edge High Resolution X-ray Absorption Spectroscopy

By Justin T. Henthorn#†, Renee J. Arias#‡, Sergey Koroidov§, Thomas Kroll?, Dimosthenis Sokaras?, Uwe Bergmann§, Douglas C. Rees*‡?, and Serena DeBeer*† from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 15, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b06988

[ASAP] Iodonitrene in Action: Direct Transformation of Amino Acids into Terminal Diazirines and 15N2-Diazirines and Their Application as Hyperpolarized Markers

By Thomas Glachet†, Hamid Marzag†, Nathalie Saraiva Rosa†, Johannes F. P. Colell‡, Guannan Zhang‡, Warren S. Warren‡, Xavier Franck§, Thomas Theis*‡?, and Vincent Reboul*† from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 15, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b07035

[ASAP] MftD Catalyzes the Formation of a Biologically Active Redox Center in the Biosynthesis of the Ribosomally Synthesized and Post-translationally Modified Redox Cofactor Mycofactocin

By Richard S. Ayikpoe† and John A. Latham*† from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 15, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b06102

[ASAP] In Situ Construction of a Cs2SnI6 Perovskite Nanocrystal/SnS2 Nanosheet Heterojunction with Boosted Interfacial Charge Transfer

By Xu-Dong Wang, Yu-Hua Huang, Jin-Feng Liao, Yong Jiang, Lei Zhou, Xiao-Yan Zhang, Hong-Yan Chen, and Dai-Bin Kuang* from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 15, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b04482

[ASAP] The Photoaddition of a Psoralen to DNA Proceeds via the Triplet State

By Janina Diekmann†, Julia Gontcharov‡, Sascha Fro¨bel†§, Christian Torres Ziegenbein†?, Wolfgang Zinth‡, and Peter Gilch*† from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 15, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b06521

The idiosyncratic self-cleaning cycle of bacteria on regularly arrayed mechano-bactericidal nanostructures

By Elena P. Ivanova from RSC - Nanoscale latest articles. Published on Aug 15, 2019.

Nanoscale, 2019, Accepted Manuscript
DOI: 10.1039/C9NR05923G, Paper
Duy H. K. Nguyen, Christian Loebbe, Denver Paige Linklater, Vladimir A. Baulin, Saulius Juodkazis, Xiumei Xu, Nandi Vrancken, Shane Maclaughlin, Tomas Katkus, Russell J. Crawford, Elena P. Ivanova
Nanostructured mechano-bactericidal surfaces represent a promising technology to prevent the incidence of microbial contamination on a variety of surfaces and to avoid bacterial infection, particularly with antibiotic resistant strains. In...
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Electrodynamic-Contact-Line-Lithography with Nematic Liquid Crystal for Template-Less E-writing of Mesopatterns on Soft Surfaces

By Partho Sarathi Gooh Pattader from RSC - Nanoscale latest articles. Published on Aug 15, 2019.

Nanoscale, 2019, Accepted Manuscript
DOI: 10.1039/C9NR05729C, Paper
Pritam Roy, Rabibrata Mukherjee, Dipankar Bandyopadhyay, Partho Sarathi Gooh Pattader
We report the development of a single-step, template-less and fast pathway, namely, Electrodynamic-Contact-Line-Lithography (ECLL), to write micro to nanopatterns on the surface of a soft polymer film. As a model...
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Gas-generating nanoparticles for contrast-enhanced ultrasound imaging

By Stanislav Emelianov from RSC - Nanoscale latest articles. Published on Aug 15, 2019.

Nanoscale, 2019, Accepted Manuscript
DOI: 10.1039/C9NR04471J, Communication
In-Cheol Sun, Stanislav Emelianov
We present a gas-generating solid nanoparticle as a new concept of the ultrasound contrast agent. The developed nanoparticles are sufficiently small (less than 100 nm in diameter) to escape vasculature...
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Realizing giant tunneling electroresistance in two-dimensional graphene/BiP ferroelectric tunnel junction

By Zhi Zeng from RSC - Nanoscale latest articles. Published on Aug 15, 2019.

Nanoscale, 2019, Accepted Manuscript
DOI: 10.1039/C9NR01656B, Paper
Lili Kang, Peng Jiang, Ning Cao, Hua Hao, Xiaohong Zheng, Lei Zhang, Zhi Zeng
Ferroelectric tunnel junctions (FTJs) composed by sandwiching a thin ferroelectric layer between two leads have attracted great interest for their potential applications in nonvolatile memories due to tunnel electroresistance (TER)...
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3D Hybrid Networks of Gold Nanoparticles: Mechanoresponsive Electrical Humidity Sensors with On-Demand Performances

By Paolo Samorì from RSC - Nanoscale latest articles. Published on Aug 15, 2019.

Nanoscale, 2019, Accepted Manuscript
DOI: 10.1039/C9NR05336K, Paper
Marco Squillaci, Marc-Antoine Stoeckel, Paolo Samorì
We have engineered macroscopic 3D porous networks of gold nanoparticles (AuNPs) chemically interconnected by di-thiolated ethylene glycol oligomers. The formation of such superstructures has been followed by means of UV-Vis...
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Recent Progress of Light Manipulation Strategies in Organic and Perovskite Solar Cells

By Jianxin Tang from RSC - Nanoscale latest articles. Published on Aug 15, 2019.

Nanoscale, 2019, Accepted Manuscript
DOI: 10.1039/C9NR05663G, Review Article
Jing-De Chen, Teng-Yu Jin, Yanqing Li, Jianxin Tang
Organic and perovskite solar cells are suffering from the insufficient utilization of incident light and thus low light harvesting efficiency despite of their rapid progress in the past decade. In...
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Moist-Electric Generation

By Liangti Qu from RSC - Nanoscale latest articles. Published on Aug 15, 2019.

Nanoscale, 2019, Accepted Manuscript
DOI: 10.1039/C9NR06113D, Minireview
Jiaxin Bai, Yaxin Huang, Huhu Cheng, Liangti Qu
The exploration of green and clean energy could solve the increasingly serious problem of environmental pollution and energy crisis on the earth. Ubiquitous moist air is widely around the word,...
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Synthesis, growth mechanisms, and applications of palladium-based nanowires and other one-dimensional nanostructures

By Mark T. Swihart from RSC - Nanoscale latest articles. Published on Aug 15, 2019.

Nanoscale, 2019, Accepted Manuscript
DOI: 10.1039/C9NR05835D, Review Article
Abhishek kumar, Mohammad Moein Mohammadi, Mark T. Swihart
Palladium-based nanostructures have attracted the attention of researchers due to their useful catalytic properties and unique ability to form hydrides, which finds application in hydrogen storage and hydrogen detection. Palladium-based...
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Nanogrooved microdiscs for bottom-up modulation of osteogenic differentiation

By Joao Mano from RSC - Nanoscale latest articles. Published on Aug 15, 2019.

Nanoscale, 2019, Accepted Manuscript
DOI: 10.1039/C9NR06267J, Communication
Isabel Marinho Bjørge, Insung S. Choi, Clara R Correia, Joao Mano
Grooved topographical features have effectively modulated cell differentiation on two-dimensional substrates. To transpose patterning into a 3D context, nanogrooved microdiscs, “topodiscs”, are produced as cell-carriers for bottom-up cell-mediated assembly. While...
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Enabling Superior Electrochemical Properties for Highly Efficient Potassium Storage via Impregnating Ultrafine Sb Nanocrystals within Nanochannel‐Containing Carbon Nanofibers

By Xiaosi Zhou, Xufang Ge, Shuhu Liu, Man Qiao, Yichen Du, Yafei Li, Jianchun Bao from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 14, 2019.

Antimony (Sb)‐based nanocomposites have emerged as an attractive class of anode materials for batteries as they exhibit large theoretical capacity and impressive working voltage. However, the tardy potassium ion diffusion characteristic, unstable Sb/electrolyte interphase, and huge volume variation pose a grand challenge that hinder the practical use of Sb‐based anodes for potassium‐ion batteries (PIBs). Herein, we report a simple yet robust strategy for uniformly impregnating ultrasmall Sb nanocrystals within carbon nanofibers containing an array of hollow nanochannels (denoted u‐Sb@CNFs) that resolve the issues noted above, yielding high‐performance PIBs. Remarkably, u‐Sb@CNFs can be directly employed as anode, thereby dispensing with the need for conductive additives and binders. Such judiciously crafted u‐Sb@CNF‐based anode renders a set of intriguing electrochemical properties, representing large charge capacity, unprecedented cycling stability, and outstanding rate performance. Notably, a reversible capacity of 225 mAh g−1 is retained after 2000 cycles at 1 A g−1.

Fri 29 Nov 12:00: Title to be confirmed

From All Talks (aka the CURE list). Published on Aug 14, 2019.

Title to be confirmed

Abstract not available

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Thu 10 Oct 12:00: Complexities in Neural Parsing

From All Talks (aka the CURE list). Published on Aug 14, 2019.

Complexities in Neural Parsing

Abstract not available

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Insertion of CO2 Mediated by a (Xantphos)NiI–Alkyl Species

By Justin B. Diccianni, Chunhua T. Hu, Tianning Diao from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 14, 2019.

Gathering support: The incorporation of CO2 into organometallic and organic molecules represents a sustainable way to prepare carboxylates. Demonstrated herein is that the direct reduction of (tBu‐Xantphos)NiIIBr2 by Zn affords NiI species. (tBu‐Xantphos)NiI‐Me and (tBu‐Xantphos)NiI‐Et complexes undergo fast insertion of CO2 at 22 °C, providing experimental support for the proposed mechanisms of Ni‐catalyzed carboxylation reactions. Abstract The incorporation of CO2 into organometallic and organic molecules represents a sustainable way to prepare carboxylates. The mechanism of reductive carboxylation of alkyl halides has been proposed to proceed through the reduction of NiII to NiI by either Zn or Mn, followed by CO2 insertion into NiI‐alkyl species. No experimental evidence has been previously established to support the two proposed steps. Demonstrated herein is that the direct reduction of (tBu‐Xantphos)NiIIBr2 by Zn affords NiI species. (tBu‐Xantphos)NiI‐Me and (tBu‐Xantphos)NiI‐Et complexes undergo fast insertion of CO2 at 22 °C. The substantially faster rate, relative to that of NiII complexes, serves as the long‐sought‐after experimental support for the proposed mechanisms of Ni‐catalyzed carboxylation reactions.

Conformational Re‐engineering of Porphyrins as Receptors with Switchable N–H···X‐type Binding Modes

By Karolis Norvaiša, Keith J. Flanagan, Daire Gibbons, Mathias O. Senge from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 14, 2019.

The selectivity and functional variability of porphyrin cofactors are typically based on substrate binding of metalloporphyrins wherein the pyrrole nitrogen units only serve to chelate the metal ions. Yet, using the free base porphyrin inner core system for other functions is possible through conformational engineering. As a first step towards porphyrin ‘enzyme‐like’ active centers, a structural and spectroscopic study of substrate binding to the inner core porphyrin system shows that a highly saddle distorted porphyrin with peripheral amino receptor groups [2,3,7,8,12,13,17,18‐octaethyl‐5,10,15,20‐tetrakis(2‐aminophenyl)porphyrin] coordinates analytes in a switchable manner dependent on the acidity of the solution. The supramolecular ensemble exhibits exceptionally high affinity to the pyrophosphate anion (2.26 ± 0.021)⋅109 M‐1 and does so in preference to other anions. 1H NMR spectroscopic studies provided insight into the likely mode of binding action and the characterization of atropisomers, all four of which were also studied by X‐ray crystallography.

Synthesis and Utility of a Neptunium(III) Hydrocarbyl Complex

By Justin Walensky, Alexander J. Myers, Michael L. Tarlton, Steven P. Kelley, Wayne W. Lukens from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 14, 2019.

To extend organoactinide chemistry beyond uranium, we report the first structurally characterized transuranic hydrocarbyl complex, Np[η4‐Me2NC(H)C6H5]3, 1, from reaction of NpCl4(DME)2 with four equivalents of K[Me2NC(H)C6H5]. Unlike the U(III) species, the neptunium analogue can be used to access other Np(III) complexes. The reaction of 1 with three equivalents of HE2C(2,6‐Mes2‐C6H3), E = O, S, yields [(2,6‐Mes2‐C6H3)CE2]3Np(THF)2, maintaining the trivalent oxidation state.

In operando visualization of the electrochemical formation of liquid polybromide microdroplets

By Yutong Wu, Po-Wei Huang, Yu Yan, Joshua D. Howe, Jose Martinez, Anna Marianchuk, Yamin Zhang, Hang Chen, Nian Liu from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 14, 2019.

Zn/Br flow batteries are one of the promising technologies for stationary energy storage. Bromine complexing agents have been used to form phase‐separated liquid polybromide charging products. However, dynamic and microscopic understanding of the nucleation and growth of the polybromides on the electrode is limited due to the beam‐sensitivity and complexity of polybromides and their surrounding electrolytes. In this communication, we report an in operando platform composed of dark field light microscopy and a transparent planar electrochemical cell to dynamically reveal the electrochemical nucleation and formation of polybromides. Using our platform we confirm and reveal the liquid nature, pinning effect (strong interaction with Pt), memory effect (surface residual charge products), self‐discharge of the polybromide product, and over‐oxidation as a side reaction. We also conclude that the electrochemically formed droplets are mainly MEPBr5 rather than previously reported MEPBr3 with in situ Ra‐man spectroscopy. These results provide mechanistic insight into the role of ionic liquid complexing agents and Zn/Br battery design. The in operando visualization platform can also be applied to study other unstable or transient products or intermediates in electrochemical reactions in a non‐perturbing manner.

Conformational Spin Switching and Spin‐Selective Hydrogenation of a Magnetically Bistable Carbene

By Iris Trosien, Enrique Mendez-Vega, Tobias Thomanek, Wolfram Sander from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 14, 2019.

The control of the spin states of molecules opens the path to tuning selectivity in chemical reactions and to developing novel magnetically switchable materials. 3‐Methoxy‐9‐fluorenylidene is a carbene that is generated in cryogenic matrices both in its lowest energy singlet and triplet states, and the ratio of these states can be shifted by selective irradiation. The interconversion of the nearly degenerate spin states is induced by a conformational change of the methoxy group: switching the methoxy group into the “up” position results in the singlet state and switching into the “down” position in the triplet state. The spin control via a remote functional group makes this carbene unique for the study of spin‐specific reactions, which is demonstrated for the hydrogenation reaction. Spin switching by switching the conformation of a remote functional group is a novel phenomenon with potential applications in the design of functional materials.

NHC‐Coordinated Diphosphene Stabilized Gold(I) Hydride and its Reversible Conversion to Gold(I) Formate with CO2

By Anukul Jana, Debabrata Dhara, Shubhajit Das, Swapan Pati, David Scheschkewitz, Vadapalli Chandrasekhar from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 14, 2019.

An NHC‐coordinated diphosphene is employed as ligand for the synthesis of a hydrocarbon‐soluble monomeric Au(I) hydride, which readily adds CO2 at room temperature yielding the corresponding Au(I) formate. The reversible reaction can be expedited by the addition of NHC, which induces β ‐hydride shift and the removal of CO2 from equilibrium through the formation of an NHC‐CO2 adduct. The Au(I) formate is alternatively formed by dehydrogenative coupling of the Au(I) hydride with formic acid (HCO2H), thus in total establishing a reaction sequence for the Au(I) hydride mediated dehydrogenation of HCO2H as chemical hydrogen storage material.

Molecular Design Strategy for Ordered Mesoporous Stoichiometric Metal Oxide

By Changyao Wang, Xiaoyue Wan, Linlin Duan, Peiyuan Zeng, Liangliang Liu, Dingyi Guo, Yuan Xia, Ahmed A. Elzatahry, Yongyao Xia, Wei Li, Dongyuan Zhao from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 14, 2019.

Although the construction of ordered mesoporous materials has achieved great processes, it is still a challenge to synthesize ordered mesoporous stoichiometric metal oxides via the co‐assembly method. Herein, we develop a molecular design strategy to construct ordered mesoporous Ti3+‐doped Li4Ti5O12 nanocrystal frameworks (OM‐Ti3+‐Li4Ti5O12) via the stoichiometric cationic coordination assembly process. Ti4+/Li+‐Citrate chelate is designed as a new molecular precursor, in which the citrate can not only stoichiometrically coordinate Ti4+ with Li+ homogeneously at the atomic scale, but also interact strongly with the PEO segments in the Pluronic F127. These features make the co‐assembly and crystallization process more controllable, thus benefiting for the formation of the ordered mesostructures. The resultant OM‐Ti3+‐Li4Ti5O12 shows excellent rate (143 mAh g−1 at 30 C) and cycling performances (

Cooperative Tertiary Amine/Chiral Iridium Complex Catalyzed Asymmetric [4+3] and [3+3] Annulation Reactions

By Ying-Chun Chen, Zhi-Chao Chen, Zhi Chen, Zhen-Hong Yang, Li Guo, Wei Du from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 14, 2019.

Asymmetric reactions merging organocatalysis and metal catalysis significantly broaden the organic synthesis. Nevertheless, the accomplishment of stereoselective annulations combining two types of dipole species, independently generated from the activations of organocatalysts and metal complexes, still remains as a challenging task. Here we report that Morita−Baylis−Hillman carbonates from isatins and carbamate‐functionalized allyl carbonates could be chemoselectively activated by achiral Lewis basic tertiary amines and chiral iridium complexes, respectively. Thus, the in situ formed zwitterionic allylic ylides and 1,4‐π‐allyliridium dipoles are finely assembled in a highly stereoselective [4+3] annulation pattern. Similar cooperative catalytic strategy could be applied for the reactions of Morita−Baylis−Hillman carbonates and vinyl aziridines, furnishing an asymmetric [3+3] annulation reaction also with excellent stereocontrol.

DNA origami nanoplate‐based emulsion with designed nanopore function

By Daisuke Ishikawa, Yuki Suzuki, Chikako Kurokawa, Masayuki Ohara, Misato Tsuchiya, Masamune Morita, Miho Yanagisawa, Masayuki Endo, Ryuj Kawano, Masahiro Takinoue from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 14, 2019.

Bio‐inspired functional microcapsules have attracted increasing attention in many fields from physical/chemical science to artificial cell engineering. Although the particle‐stabilised microcapsules are advantageous for their stability and functionalisation potential, versatile methods for their designable functionalisation are desired to expand their possibilities. This study reports a water‐in‐oil microdroplet stabilised with amphiphilised DNA origami nanoplates. By utilising DNA nanotechnology, DNA nanoplates were designed as a nanopore device for ion transportation and as an interface stabiliser. Microscopic examination revealed the microcapsule formed by the accumulation of amphiphilic DNA nanoplates at the oil‐water interface. Ion current measurements revealed the nanoplate pores functioned as channel to transport ions. These findings provide a general strategy for programmable design of microcapsules to engineer artificial cells and molecular robots.

Thu 14 Nov 14:30: Inequalities on projected volumes

From All Talks (aka the CURE list). Published on Aug 14, 2019.

Inequalities on projected volumes

Given $2n – 1$ real numbers $x_A$ indexed by the non-empty subsets $A \subset \{ 1,\ldots,n \}$, is it possible to construct a body $T$ in $Rn$ such that $x_A = \| T_A \|$, where $\| T_A \|$ is the $\| A \|$-dimensional volume of the projection of $T$ onto the subspace spanned by the axes of $A$? As it is more convenient to take logarithms, we denote by $\psi_n$ the set of all vectors $x$ for which there is a body $T$ such that $x_A = \log \| T_A \|$ for all $A$. Bollob\’as and Thomason showed that $\psi_n$ is containd in the polyhedral cone defined by the class of `uniform cover inequalities’. Tao and Zeng conjectured that the convex hull of $\psi_n$ is equal to the cone given by the uniform cover inequalities.

We show that this conjecture is not right, but is `nearly’ right.

Joint work with Imre Leader and Eero Raty.

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Wed 27 Nov 15:00: Messengers: Who We Listen To, Who We Don't, And Why

From All Talks (aka the CURE list). Published on Aug 14, 2019.

Messengers: Who We Listen To, Who We Don't, And Why

We live in a world where proven facts and verifiable data are freely and widely available. Why, then, are so many self-confident ignoramuses believed? Why are thoughtful experts so often dismissed? And why do seemingly irrelevant details such as a person’s height, relative wealth, or Facebook photo influence whether or not we trust what they are saying? In this talk I will discuss why people so often attend to characteristics of the messenger, rather than the content of the message, when deciding whom to listen to. In particular, I will show how the perceived status of a messenger, and the level of connectedness others feel towards them, influence how persuasive their messages will be.

Joseph Marks, MSc., is an experimental psychologist and co-author of the book Messengers: Who We Listen To, Who We Don’t, And Why (with Stephen Martin). He is currently a doctoral researcher at University College London, a visiting researcher at the Massachusetts Institute of Technology, and an Associate Consultant for INFLUENCE AT WORK (UK). His work has featured in The New York Times, Guardian, and the Harvard Business Review. Joseph holds an undergraduate degree in psychology from the University of Birmingham and a Master’s degree in Social Cognition from University College London. His research with INFLUENCE AT WORK has been applied across a variety of business and public policy settings, including financial regulation, healthcare, and public transport.

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Crystal structure of a NIR‐emitting DNA‐stabilized Ag16 nanocluster

By Cecilia Cerretani, Hiroki Kanazawa, Tom Vosch, Jiro Kondo from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 14, 2019.

In the last 15 years, scientists have used DNA as a scaffold to stabilize small, atomically monodisperse silver nanoclusters. These DNA‐templated nanoclusters have attracted a lot of attention due to their intriguing photophysical properties. Here, we describe the crystal structure of a DNA‐encapsulated, near‐infrared emitting Ag16 nanocluster (DNA‐Ag16NC) determined by X‐ray analysis. The asymmetric unit of the crystal contains two DNA‐Ag16NCs and the crystal packing between DNA‐Ag16NCs is promoted by several interactions, such as two silver‐mediated base pairs between 3’‐terminal adenines, phosphate‐Ca2+‐phosphate interaction and π‐stacking between two neighboring thymines. The individual Ag16NC is confined by two DNA decamers that take on a horse‐shoe‐like conformation. The tight wrapping of the two DNA strands around the cluster indicates that the Ag16NC is almost fully shielded from the solvent environment. The reported structural insight will enable to decipher the structure/photophysical property relationship for this class of emitters and open up a myriad of new research opportunities in fluorescence imaging and sensing using noble metal clusters in general.

A Fluorescent LCK Inhibitor that Exhibits Diagnostic Changes in Emission Upon Binding the Kinase Enzyme

By Cassandra Lee Fleming, Patrick A Sandoz, Tord Inghardt, Björn Önfelt, Morten Grøtli, Joakim Andreasson from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 14, 2019.

The development of a fluorescent LCK inhibitor that exhibits favourable solvatochromic properties upon binding the kinase enzyme is described. Fluorescent properties were realised through the inclusion of a Prodan‐derived fluorophore into the pharmacophore of the ATP‐competitive kinase inhibitor. Fluorescence titration experiments exemplify the solvatochromic properties of the inhibitor, in which dramatic increase in emission intensity and hypsochromic shift in emission maxima are clearly observed upon binding LCK. Microscopy experiments in cellular contexts together with flow cytometry show that the fluorescence intensity of the inhibitor correlates with the LCK concentration. Furthermore, multiphoton microscopy experiments demonstrate both the rapid cellular uptake of the inhibitor and that the two‐photon cross section of the inhibitor is amenable for excitation at 700 nm.

Quantitative Synthesis of Temperature‐responsive Polymersomes by Multiblock Polymerization

By Xiaoling Liu, Dongxu Zhou, Yunbo Feng, Jing Gou, Chenxi Li, Chao He, Weifeng Zhao, Shudong Sun, Changsheng Zhao, Dietmar Appelhans, Brigitte Voit from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 14, 2019.

The current challenge for polymersomes is to prepare amphiphilic block polymers with not only well‐defined molecular weight, but also precisely high‐order multiblock structure in terms of the distribution of monomeric units along the chain. Here, we describe a synthesis of temperature‐responsive polymersomes with precisely defined membrane structures using high‐precision amphiphilic multiblock polymer via aqueous single electron transfer living radical polymerization (SET‐LRP) in which poly(ethylene glycol) (PEG) macromolecules are used as initiators. We develop a one‐pot, rapid and multistep sequential polymerization process with yields >99% within 30 min for each block, giving access to a wide range of high‐precision multiblock polymers with very narrow molecular weight distributions (Ð ≤ 1.14). Synthesized multiblock polymers are used to form nano‐sized polymersomes which are highly promising as smart carriers for high loading and triggered release of biopharmaceutics such as pharmaceutical proteins and peptides. This synthesis approach is environmentally friendly, fully translation and thus represents a significant advance in the design and synthesis of a new generation of polymer nanomaterials with precisely defined structures, which is highly attractive for applications in nanotechnology.

Tue 05 Nov 14:00: Title to be confirmed

From All Talks (aka the CURE list). Published on Aug 14, 2019.

Title to be confirmed

Abstract not available

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Observation of the Low‐Frequency Spectrum of the Water Dimer as a Sensitive Test of the Water Dimer Potential and Dipole Moment Surfaces

By Raffael Schwan, Chen Qu, Devendra Mani, Nitish Pal, Lex van der Meer, Britta Redlich, Claude Leforestier, Joel M. Bowman, Gerhard Schwaab, Martina Havenith from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 14, 2019.

The intermolecular modes of the water dimer in the frequency region from 70 to 550 cm−1 were recorded. Observed bands were assigned to donor torsion, acceptor wag, acceptor twist, intermolecular stretch, donor torsion overtone, and in‐plane and out‐of‐plane vibrational modes. This data provides a test for water potentials and dipole moment surfaces. Calculations of the IR spectrum are presented using molecular dynamics approaches. Abstract Using the helium nanodroplet isolation setup at the ultrabright free‐electron laser source FELIX in Nijmegen (BoHeNDI@FELIX), the intermolecular modes of water dimer in the frequency region from 70 to 550 cm−1 were recorded. Observed bands were assigned to donor torsion, acceptor wag, acceptor twist, intermolecular stretch, donor torsion overtone, and in‐plane and out‐of‐plane librational modes. This experimental data set provides a sensitive test for state‐of‐the‐art water potentials and dipole moment surfaces. Theoretical calculations of the IR spectrum are presented using high‐level quantum and approximate quasiclassical molecular dynamics approaches. These calculations use the full‐dimensional ab initio WHHB potential and dipole moment surfaces. Based on the experimental data, a considerable increase of the acceptor switch and a bifurcation tunneling splitting in the librational mode is deduced, which is a consequence of the effective decrease in the tunneling barrier.

Copper‐Catalyzed Asymmetric Annulation Reactions of Carbenes with 2‐Iminyl‐ or 2‐Acyl‐Substituted Phenols: Convenient Access to Enantioenriched 2,3‐Dihydrobenzofurans

By Xin‐Shen Liang, Rui‐Dong Li, Xiao‐Chen Wang from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 14, 2019.

Full circle: A Cu‐catalyzed enantioselective annulation of aryldiazoacetates with 2‐iminyl‐ or 2‐acyl‐substituted phenols has been developed to prepare enantioenriched 2,3‐dihydrobenzofurans. In this reaction, the Cu catalyst first induces carbene formation, and then functions as a Lewis acid to activate the electrophile and control the diastereo‐ and enantioselectivity. Abstract We have developed a method for the highly diastereo‐ and enantioselective construction of 2,3‐dihydrobenzofurans bearing tetrasubstituted carbon stereocenters by means of annulation reactions between carbenes and 2‐iminyl‐ or 2‐acyl‐substituted phenols through catalysis by readily accessible copper(I)/bisoxazoline catalysts under mild conditions. These reactions feature a unique mechanism in which the copper catalyst serves a dual function: first it reacts with the diazo compound to generate a metal carbene, and second, upon formation of an oxonium ylide, it acts as a Lewis acid to activate the imine or ketone for diastereo‐ and enantioselective cyclization.

Coordination Assisted Distal C−H Alkylation of Fused Heterocycles

By Kankanala Ramakrishna, Jyoti Prasad Biswas, Sadhan Jana, Tapas Kumar Achar, Sandip Porey, Debabrata Maiti from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 14, 2019.

Distal C−H alkylation (C‐5 of quinoline and thiazole, C‐7 of benzothiazole and benzoxazole) of heterocycles is reported. Upon complexation with heterocyclic substrate, nitrile DG in template directs the metal catalyst towards close vicinity of the specific distal C−H bond of the heterocycles. The hypothesized pathway has been supported by various X‐ray crystallographically characterized intermediates. Abstract Distal C−H bond functionalization of heterocycles remained extremely challenging with covalently attached directing groups (DG). Lack of proper site for DG attachment and inherent catalyst poisoning by heterocycles demand alternate routes for site selective functionalization of their distal C−H bonds. Utilizing non‐productive coordinating property to hold the heterocycle into the cavity of a template system in a host–guest manner, we report distal C−H alkylation (C‐5 of quinoline and thiazole, C‐7 of benzothiazole and benzoxazole) of heterocycles. Upon complexation with heterocyclic substrate, nitrile DG in template directs the metal catalyst towards close vicinity of the specific distal C−H bond of the heterocycles. Our hypothesized pathway has been supported by various X‐ray crystallographically characterized intermediates.

Channel‐Rich RuCu Nanosheets for pH‐Universal Overall Water Splitting Electrocatalysis

By Qing Yao, Bolong Huang, Nan Zhang, Mingzi Sun, Qi Shao, Xiaoqing Huang from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 14, 2019.

Channel rich RuCu nanosheets (NSs) have been successfully prepared and applied as a highly active and stable bifunctional electrocatalyst for the oxygen evolution reaction, hydrogen evolution reaction, as well as overall water splitting. This system is one of the best electrocatalysts reported to date. Abstract Channel‐rich RuCu snowflake‐like nanosheets (NSs) composed of crystallized Ru and amorphous Cu were used as efficient electrocatalysts for oxygen evolution reaction (OER), hydrogen evolution reaction (HER), and overall water splitting in pH‐universal electrolytes. The optimized RuCu NSs/C‐350 °C and RuCu NSs/C‐250 °C show attractive activities of OER and HER with low overpotentials and small Tafel slopes, respectively. When applied to overall water splitting, the optimized RuCu NSs/C can reach 10 mA cm−2 at cell voltages of only 1.49, 1.55, 1.49 and 1.50 V in 1 m KOH, 0.1 m KOH, 0.5 m H2SO4 and 0.05 m H2SO4, respectively, much lower than those of commercial Ir/C∥Pt/C. The optimized electrolyzer exhibits superior durability with small potential change after up to 45 h in 1 m KOH, showing a class of efficient functional electrocatalysts for overall water splitting.

Tetrahydroxy‐Perylene Bisimide Embedded in Zinc Oxide Thin Film as Electron Transporting Layer for High Performance Non‐Fullerene Organic Solar Cells

By Xinbo Wen, Agnieszka Nowak‐Król, Oliver Nagler, Felix Kraus, Na Zhu, Nan Zheng, Matthias Müller, David Schmidt, Zengqi Xie, Frank Würthner from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 14, 2019.

A photoconductive ZnO interlayer was generated by coordinative binding of zinc ions to perylene bisimide dyes bearing four hydroxy groups in bay area. With this dye‐sensitized interlayer improvement of polymer solar cells was achieved, leading to power conversion efficiencies close to 16 %. Abstract By introduction of four hydroxy (HO) groups into the two perylene bisimide (PBI) bay areas, new HO‐PBI ligands were obtained which upon deprotonation can complex ZnII ions and photosensitize semiconductive zinc oxide thin films. Such coordination is beneficial for dispersing PBI photosensitizer molecules evenly into metal oxide films to fabricate organic–inorganic hybrid interlayers for organic solar cells. Supported by the photoconductive effect of the ZnO:HO‐PBI hybrid interlayers, improved electron collection and transportation is achieved in fullerene and non‐fullerene polymer solar cell devices, leading to remarkable power conversion efficiencies of up to 15.95 % for a non‐fullerene based organic solar cell.

Structural and Computational Analysis of 2‐Halogeno‐Glycosyl Cations in the Presence of a Superacid: An Expansive Platform

By Ludivine Lebedel, Ana Ardá, Amélie Martin, Jérôme Désiré, Agnès Mingot, Marialuisa Aufiero, Nuria Aiguabella Font, Ryan Gilmour, Jesus Jiménez‐Barbero, Yves Blériot, Sébastien Thibaudeau from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 14, 2019.

Influential halogens: Halogen substitution effects on the conformation of superacid‐generated glucosyl, galactosyl, and mannosyl cations are described. The 2‐bromo derivatives display intramolecular stabilization of the glycosyl cations. Introducing an electron‐withdrawing fluorine atom at C2 influences the oxocarbenium ion reactivity in a superacid, with quenching by weakly coordinating SbF6− anions. Abstract An expansive NMR‐based structural analysis of elusive glycosyl cations derived from natural and non‐natural monosaccharides in superacids is disclosed. For the first time, it has been possible to explore the consequence of deoxygenation and halogen substitution at the C2 position in a series of 2‐halogenoglucosyl, galactosyl, and mannosyl donors in the condensed phase. These cationic intermediates were characterized using low‐temperature in situ NMR experiments supported by DFT calculations. The 2‐bromo derivatives display intramolecular stabilization of the glycosyl cations. Introducing a strongly electron‐withdrawing fluorine atom at C2 exerts considerable influence on the oxocarbenium ion reactivity. In a superacid, these oxocarbenium ions are quenched by weakly coordinating SbF6− anions, thereby demonstrating their highly electrophilic character and their propensity to interact with poor nucleophiles.

A Promising Carbon/g‐C3N4 Composite Negative Electrode for a Long‐Life Sodium‐Ion Battery

By Guo‐Ming Weng, Yu Xie, Hang Wang, Christopher Karpovich, Jason Lipton, Junqing Zhu, Jaemin Kong, Lisa D. Pfefferle, André D. Taylor from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 14, 2019.

Flatland composites: Low‐cost carbon/graphitic carbon nitride (C/g‐C3N4) composites can be used as the negative electrode for a long‐life sodium‐ion battery. Abstract 2D graphitic carbon nitride (g‐C3N4) nanosheets are a promising negative electrode candidate for sodium‐ion batteries (NIBs) owing to its easy scalability, low cost, chemical stability, and potentially high rate capability. However, intrinsic g‐C3N4 exhibits poor electronic conductivity, low reversible Na‐storage capacity, and insufficient cyclability. DFT calculations suggest that this could be due to a large Na+ ion diffusion barrier in the innate g‐C3N4 nanosheet. A facile one‐pot heating of a mixture of low‐cost urea and asphalt is strategically applied to yield stacked multilayer C/g‐C3N4 composites with improved Na‐storage capacity (about 2 times higher than that of g‐C3N4, up to 254 mAh g−1), rate capability, and cyclability. A C/g‐C3N4 sodium‐ion full cell (in which sodium rhodizonate dibasic is used as the positive electrode) demonstrates high Coulombic efficiency (ca. 99.8 %) and a negligible capacity fading over 14 000 cycles at 1 A g−1.

Rational Design of Specific Recognition Molecules for Simultaneously Monitoring of Endogenous Polysulfide and Hydrogen Sulfide in the Mouse Brain

By Hui Dong, Qi Zhou, Limin Zhang, Yang Tian from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 14, 2019.

A single electrochemical sensor was created for simultaneous detection of H2Sn and H2S in the brain. The expression of TRPA1 channel was found to be positively correlated with the levels of H2Sn in two brain disease models under ischemia and Alzheimer's diseases, and H2Sn is more active for expression of TRPA1 protein than that of H2S. Abstract A biosensor was created for the simultaneous monitoring of endogenous H2Sn and H2S in mouse brains and exploring their roles in activation of the TRPA1 channel under two types of brain disease models: ischemia and Alzheimer's disease (AD). Based on DFT calculations and electrochemical measurements, two probes, 3,4‐bis((2‐fluoro‐5‐nitrobenzoyl)oxy)‐benzoic acid (MPS‐1) and N‐(4‐(2,5‐dinitrophenoxy) phenyl)‐5‐(1, 2‐dithiolan‐3‐yl)pentanamide (MHS‐1), were synthesized for specific recognition of H2Sn and H2S. Through co‐assembly of the two probes at the mesoporous gold film with good anti‐biofouling ability and electrocatalytic activity, this microsensor showed high selectivity for H2Sn and H2S against potential biological interferences. The biosensor can simultaneously determine the concentration of H2Sn from 0.2 to 50 μm, as well as that of H2S from 0.2 to 40 μm. The expression of TRPA1 protein positively correlated with levels of H2Sn under both ischemia and AD.

Topotactic Synthesis of Phosphabenzene‐Functionalized Porous Organic Polymers: Efficient Ligands in CO2 Conversion

By Zhenzhen Yang, Hao Chen, Bo Li, Wei Guo, Kecheng Jie, Yifan Sun, De‐en Jiang, Ilja Popovs, Sheng Dai from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 14, 2019.

Top of the POPs: A topotactical two‐step synthetic pathway has been developed for the preparation of porous phosphabenzene‐functionalized polymers under metal‐free conditions. These porous organic polymers (POPs) exhibit high CO2 uptake capacity and act as efficient heterogeneous catalysts for amine formylation when doped with a small amount of ruthenium. Abstract Progress toward the preparation of porous organic polymers (POPs) with task‐specific functionalities has been exceedingly slow—especially where polymers containing low‐oxidation phosphorus in the structure are concerned. A two‐step topotactic pathway for the preparation of phosphabenzene‐based POPs (Phos‐POPs) under metal‐free conditions is reported, without the use of unstable phosphorus‐based monomers. The synthetic route allows additional functionalities to be introduced into the porous polymer framework with ease. As an example, partially fluorinated Phos‐POPs (F‐Phos‐POPs) were obtained with a surface area of up to 591 m2 g−1. After coordination with Ru species, a Ru/F‐Phos‐POPs catalyst exhibited high catalytic efficiency in the formylation of amines (turnover frequency up to 204 h−1) using a CO2/H2 mixture, in comparison with the non‐fluorinated analogue (43 h−1) and a Au/TiO2 heterogeneous catalysts reported previously (

The Kirkendall Effect for Engineering Oxygen Vacancy of Hollow Co3O4 Nanoparticles toward High‐Performance Portable Zinc–Air Batteries

By Dongxiao Ji, Li Fan, Lu Tao, Yingjun Sun, Menggang Li, Guorui Yang, Thang Q. Tran, Seeram Ramakrishna, Shaojun Guo from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 14, 2019.

Controllable oxygen vacancy defects were introduced into the hollow Co3O4 nanoparticles through the regulation of nanoscale Kirkendall effect. This dramatically enhanced the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) activities, leading to superior Zn–air battery performance. Abstract Structure and defect control are widely accepted effective strategies to manipulate the activity and stability of catalysts. On a freestanding hierarchically porous carbon microstructure, the tuning of oxygen vacancy in the embedded hollow cobaltosic oxide (Co3O4) nanoparticles is demonstrated through the regulation of nanoscale Kirkendall effect. Starting with the embedded cobalt nanoparticles, the concentration of oxygen‐vacancy defect can vary with the degree of Kirkendall oxidation, thus regulating the number of active sites and the catalytic performances. The optimized freestanding catalyst shows among the smallest reversible oxygen overpotential of 0.74 V for catalyzing oxygen reduction/evolution reactions in 0.1 m KOH. Moreover, the catalyst shows promise for substitution of noble metals to boost cathodic oxygen reactions in portable zinc–air batteries. This work provides a strategy to explore catalysts with controllable vacancy defects and desired nano‐/microstructures.

16.67% Rigid and 14.06% Flexible Organic Solar Cells Enabled by Ternary Heterojunction Strategy

By Tingting Yan, Wei Song, Jiaming Huang, Ruixiang Peng, Like Huang, Ziyi Ge from Wiley: Advanced Materials: Table of Contents. Published on Aug 14, 2019.

High efficiencies of 16.67% (certified as 16.0%) for rigid and 14.06% for flexible organic solar cells (OSCs) are achieved by employing a PM6:Y6:PC71BM ternary system. This is a promising ternary heterojunction strategy for the development of highly efficient rigid and flexible OSCs. Abstract Ternary heterojunction strategies appear to be an efficient approach to improve the efficiency of organic solar cells (OSCs) through harvesting more sunlight. Ternary OSCs are fabricated by employing wide bandgap polymer donor (PM6), narrow bandgap nonfullerene acceptor (Y6), and PC71BM as the third component to tune the light absorption and morphologies of the blend films. A record power conversion efficiency (PCE) of 16.67% (certified as 16.0%) on rigid substrate is achieved in an optimized PM6:Y6:PC71BM blend ratio of 1:1:0.2. The introduction of PC71BM endows the blend with enhanced absorption in the range of 300–500 nm and optimises interpenetrating morphologies to promote photogenerated charge dissociation and extraction. More importantly, a PCE of 14.06% for flexible ITO‐free ternary OSCs is obtained based on this ternary heterojunction system, which is the highest PCE reported for flexible state‐of‐the‐art OSCs. A very promising ternary heterojunction strategy to develop highly efficient rigid and flexible OSCs is presented.

Spectroscopic Characterization of an Eight‐Iron Nitrogenase Cofactor Precursor That Lacks the “9th Sulfur”

By Andrew J Jasniewski, Jarett Wilcoxen, Kazuki Tanifuji, Britt Hedman, Keith O Hodgson, R David Britt, Yilin Hu, Markus Walter Ribbe from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 14, 2019.

Nitrogenase catalyzes the reduction of N2 to NH₄+ at its cofactor site. Designated the M‐cluster, this [MoFe₇S₉C(R‐homocitrate)] cofactor is synthesized via transformation of a [Fe₄S₄] cluster pair into an [Fe₈S₉C] precursor (designated the L‐cluster) prior to insertion of Mo and homocitrate. Here we report the characterization of an eight‐iron cofactor precursor (designated the L*‐cluster), which is proposed to have a composition of [Fe₈S₈C] and lack the “9th sulfur” in the belt region of the L‐cluster. Our X‐ray absorption and electron spin echo envelope modulation analyses strongly suggest that the L*‐cluster represents a structural homolog to the L‐cluster except for the missing belt sulfur. The absence of a belt sulfur from the L*‐cluster may prove beneficial for labeling the catalytically important belt region, which could in turn facilitate investigations into the reaction mechanism of nitrogenase.

[ASAP] Stretchable and Transparent Kirigami Conductor of Nanowire Percolation Network for Electronic Skin Applications

By Phillip Won†#, Jung Jae Park†#, Taemin Lee†, Inho Ha†, Seonggeun Han†, Mansoo Choi†, Jinhwan Lee‡, Sukjoon Hong§, Kyu-Jin Cho†, and Seung Hwan Ko*†?? from Nano Letters: Latest Articles (ACS Publications). Published on Aug 14, 2019.

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Nano Letters
DOI: 10.1021/acs.nanolett.9b02014

[ASAP] Absence of Quantum-Confined Stark Effect in GaN Quantum Disks Embedded in (Al,Ga)N Nanowires Grown by Molecular Beam Epitaxy

By C. Sinito*†§, P. Corfdir†?, C. Pfu¨ller†, G. Gao†?, J. Bartolome´†#, S. Ko¨lling‡, A. Rodil Doblado‡?, U. Jahn†, J. La¨hnemann†, T. Auzelle†, J. K. Zettler†?, T. Flissikowski†, P. Koenraad‡, H. T. Grahn†, L. Geelhaar†, S. Ferna´ndez-Garrido†?, and O. Brandt*† from Nano Letters: Latest Articles (ACS Publications). Published on Aug 14, 2019.

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Nano Letters
DOI: 10.1021/acs.nanolett.9b01521

[ASAP] Biocompatible Quantum Funnels for Neural Photostimulation

By Houman Bahmani Jalali†, Onuralp Karatum‡, Rustamzhon Melikov‡, Ugur Meric Dikbas§, Sadra Sadeghi?, Erdost Yildiz?, Itir Bakis Dogru†, Guncem Ozgun Eren†, Cagla Ergun#, Afsun Sahin??, Ibrahim Halil Kavakli§#, and Sedat Nizamoglu*†‡? from Nano Letters: Latest Articles (ACS Publications). Published on Aug 14, 2019.

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Nano Letters
DOI: 10.1021/acs.nanolett.9b01697

[ASAP] Unidirectional Spin–Orbit Interaction Induced by the Line Defect in Monolayer Transition Metal Dichalcogenides for High-Performance Devices

By Xiaoyin Li†§, Shunhong Zhang‡§, Huaqing Huang§, Lin Hu§?, Feng Liu*§, and Qian Wang*† from Nano Letters: Latest Articles (ACS Publications). Published on Aug 14, 2019.

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Nano Letters
DOI: 10.1021/acs.nanolett.9b01812

[ASAP] Ultrabright and Stable Luminescent Labels for Correlative Cathodoluminescence Electron Microscopy Bioimaging

By Kerda Keevend†‡§, Laurits Puust?, Karoliine Kurvits?, Lukas R. H. Gerken†§, Fabian H. L. Starsich?, Jian-Hao Li†§, Martin T. Matter†§?, Anastasia Spyrogianni#, Georgios A. Sotiriou?, Michael Stiefel??, and Inge K. Herrmann*†§? from Nano Letters: Latest Articles (ACS Publications). Published on Aug 14, 2019.

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Nano Letters
DOI: 10.1021/acs.nanolett.9b01819

[ASAP] Tailor Plasmons in Pentacene/Graphene Heterostructures with Interlayer Electron Transfer

By F. Hu†‡#, M. Kim†‡#, Y. Zhang§, Y. Luan†‡, K. M. Ho†‡, Y. Shi§, C. Z. Wang*†‡, X. Wang*§, and Z. Fei*†‡ from Nano Letters: Latest Articles (ACS Publications). Published on Aug 14, 2019.

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Nano Letters
DOI: 10.1021/acs.nanolett.9b01945

[ASAP] Fiber-Integrated Reversibly Wavelength-Tunable Nanowire Laser Based on Nanocavity Mode Coupling

By Ming-Hua Zhuge†, Zongyin Yang‡, Jianpei Zhang§, Yazhi Zheng†, Qinghai Song?, Chenlei Pang†, Xu Liu†, Salman Ullah†, Caofeng Pan?, Nagarajan Raghavan#, Xing-Hong Zhang?, Haifeng Li†, Yaoguang Ma*†, Qing Yang*†?, and Tawfique Hasan‡ from ACS Nano: Latest Articles (ACS Publications). Published on Aug 14, 2019.

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ACS Nano
DOI: 10.1021/acsnano.9b05110

[ASAP] Transitional Metal Catalytic Pyrite Cathode Enables Ultrastable Four-Electron-Based All-Solid-State Lithium Batteries

By Hongli Wan†‡, Gaozhan Liu†‡, Yanle Li†§, Wei Weng†‡, Jean Pierre Mwizerwa†‡, Ziqi Tian*†§, Liang Chen†‡, and Xiayin Yao*†‡ from ACS Nano: Latest Articles (ACS Publications). Published on Aug 14, 2019.

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ACS Nano
DOI: 10.1021/acsnano.9b04538

[ASAP] Dimensional Crossover and Topological Phase Transition in Dirac Semimetal Na3Bi Films

By Huinan Xia†#, Yang Li‡§?#, Min Cai†, Le Qin†, Nianlong Zou‡§?, Lang Peng†, Wenhui Duan‡§?, Yong Xu*‡§?, Wenhao Zhang*†, and Ying-Shuang Fu*† from ACS Nano: Latest Articles (ACS Publications). Published on Aug 14, 2019.

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ACS Nano
DOI: 10.1021/acsnano.9b04933

[ASAP] Single Atomic Vacancy Catalysis

By Jieun Yang†, Yan Wang†, Maureen J. Lagos‡, Viacheslav Manichev§¶, Raymond Fullon?, Xiuju Song#, Damien Voiry?, Sudip Chakraborty?, Wenjing Zhang#, Philip E. Batson¶?, Leonard Feldman¶??, Torgny Gustafsson¶?, and Manish Chhowalla*†# from ACS Nano: Latest Articles (ACS Publications). Published on Aug 14, 2019.

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ACS Nano
DOI: 10.1021/acsnano.9b05226

[ASAP] Surface-Plasmon-Induced Ammonia Decomposition on Copper: Excited-State Reaction Pathways Revealed by Embedded Correlated Wavefunction Theory

By Junwei Lucas Bao† and Emily A. Carter*‡ from ACS Nano: Latest Articles (ACS Publications). Published on Aug 14, 2019.

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ACS Nano
DOI: 10.1021/acsnano.9b05030

[ASAP] Aluminum Nanocubes Have Sharp Corners

By Benjamin D. Clark†‡, Christian R. Jacobson†‡, Minhan Lou§?, David Renard†‡, Gang Wu?, Luca Bursi§‡, Arzeena S. Ali†‡, Dayne F. Swearer†‡, Ah-Lim Tsai?, Peter Nordlander§?‡, and Naomi J. Halas*†?‡ from ACS Nano: Latest Articles (ACS Publications). Published on Aug 14, 2019.

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ACS Nano
DOI: 10.1021/acsnano.9b05277

[ASAP] Rewritable, Printable Conducting Liquid Metal Hydrogel

By Jung-Eun Park†§, Han Sol Kang†§, Jonghyek Baek‡, Tae Hyun Park†, Seunghee Oh‡, Hyungsuk Lee‡, Min Koo*†, and Cheolmin Park*† from ACS Nano: Latest Articles (ACS Publications). Published on Aug 14, 2019.

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ACS Nano
DOI: 10.1021/acsnano.9b03405

[ASAP] The Role of Protein Thermodynamics and Primary Structure in Fibrillogenesis of Variable Domains from Immunoglobulin Light Chains

By Enrico Rennella*†, Gareth J. Morgan‡§, Nicholas Yan‡, Jeffery W. Kelly‡, and Lewis E. Kay*†? from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 14, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b05499

[ASAP] Quantum Effects on H2 Diffusion in Zeolite RHO: Inverse Kinetic Isotope Effect for Sieving

By Lu Gem Gao†‡, Rui Ming Zhang†, Xuefei Xu*†, and Donald G. Truhlar*‡ from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 14, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b06506

[ASAP] C–N Cross-Couplings for Site-Selective Late-Stage Diversification via Aryl Sulfonium Salts

By Pascal S. Engl‡, Andreas P. Ha¨ring‡, Florian Berger, Georg Berger, Alberto Pe´rez-Bitria´n, and Tobias Ritter* from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 14, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b07323

[ASAP] Role of the Carboxylate in Enzyme-Catalyzed Decarboxylation of Orotidine 5'-Monophosphate: Transition State Stabilization Dominates Over Ground State Destabilization

By Bogdana Goryanova, Tina L. Amyes, and John P. Richard* from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 14, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b04823

[ASAP] Anisotropic Polyoxometalate Cages Assembled via Layers of Heteroanion Templates

By Qi Zheng†, Manuel Kupper†, Weimin Xuan†, Hirofumi Oki‡, Ryo Tsunashima‡, De-Liang Long*†, and Leroy Cronin*† from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 14, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b04533

[ASAP] Cyclic Sulfenyl Thiocarbamates Release Carbonyl Sulfide and Hydrogen Sulfide Independently in Thiol-Promoted Pathways

By Yu Zhao, Andrea K. Steiger, and Michael D. Pluth* from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 14, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b06319

[ASAP] Iron(III) Speciation Observed at Aqueous and Glycerol Surfaces: Vibrational Sum Frequency and X-ray

By Lu Lin, Jakub Husek, Somnath Biswas, Stephen M. Baumler, Tehseen Adel, Ka Chon Ng, L. Robert Baker, and Heather C. Allen* from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 14, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b05231

[ASAP] In Situ Small-Angle X-ray Scattering Studies During Reversible Addition–Fragmentation Chain Transfer Aqueous Emulsion Polymerization

By Emma E. Brotherton†, Fiona L. Hatton*†§, Amy A. Cockram†, Matthew J. Derry†, Adam Czajka†, Erik J. Cornel†, Paul D. Topham‡, Oleksandr O. Mykhaylyk†, and Steven P. Armes*† from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 14, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b06788

[ASAP] Ligand-Induced Surface Charge Density Modulation Generates Local Type-II Band Alignment in Reduced-Dimensional Perovskites

By Rafael Quintero-Bermudez†?, Andrew H. Proppe†‡?, Arup Mahata§??, Petar Todorovic´´†, Shana O. Kelley‡?, Filippo De Angelis*§?#, and Edward H. Sargent*† from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 14, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b04801

[ASAP] Monitoring DNA–Ligand Interactions in Living Human Cells Using NMR Spectroscopy

By Michaela Krafcikova†#?, Simon Dzatko†?, Coralie Caron‡§, Anton Granzhan‡§, Radovan Fiala†, Tomas Loja†, Marie-Paule Teulade-Fichou‡§, Tomas Fessl?, Robert Ha¨nsel-Hertsch?, Jean-Louis Mergny‡§#, Silvie Foldynova-Trantirkova*#, and Lukas Trantirek*†# from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 14, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b03031

[ASAP] Rationalizing the Hot-Carrier-Mediated Reaction Mechanisms and Kinetics for Ammonia Decomposition on Ruthenium-Doped Copper Nanoparticles

By Junwei Lucas Bao† and Emily A. Carter*‡ from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 14, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b06804

GDCh Science Forum Chemistry 2019

By from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 13, 2019.

A Transparent Photonic Artificial Visual Cortex

By Mohit Kumar, Tapobrata Som, Joondong Kim from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

A proof‐of‐concept all‐oxide‐based highly transparent heterostructure is proposed and demonstrated, which mimics primitive functions of the visual cortex. Orientation selectivity and spatiotemporal processing similar to that of the visual cortex are demonstrated under the self‐biased condition, illustrating an energy‐efficient approach for neuromorphic computing. The highly transparent, self‐biased, photonic triggered device paves the way for the advancement of energy‐efficient neuromorphic visual inspection. Abstract Mimicking brain‐like functionality with an electronic device is an essential step toward the design of future technologies including artificial visual and memory applications. Here, a proof‐of‐concept all‐oxide‐based (NiO/TiO2) highly transparent (54%) heterostructure is proposed and demonstrated, which mimics the primitive functions of the visual cortex. Specifically, orientation selectivity and spatiotemporal processing similar to that of the visual cortex are demonstrated using direct optical stimuli under the self‐biased condition due to photovoltaic effect, illustrating an energy‐efficient approach for neuromorphic computing. The photocurrent of the device can be modulated from zero to 80 µA by simply rotating the slit by 90°. The device shows fast rise and fall times of 3 and 6 ms, respectively. Based on Kelvin probe force measurements, the observed results are attributed to a lateral photovoltaic effect. This highly transparent, self‐biased, photonic triggered device paves the way for the advancement of energy‐efficient neuromorphic computation.

1D Carbon‐Based Nanocomposites for Electrochemical Energy Storage

By Changwei Shi, Kwadwo Asare Owusu, Xiaoming Xu, Ting Zhu, Guobin Zhang, Wei Yang, Liqiang Mai from Wiley: Small: Table of Contents. Published on Aug 13, 2019.

1D carbon‐based nanocomposites are categorized into four configurations, including 1D carbon‐embedded, carbon‐coated, carbon‐encapsulated, and carbon‐supported nanostructures. The important advances in the synthesis and applications of 1D carbon‐based nanocomposites for different energy storage systems, and in situ characterization techniques for understanding the fundamental mechanism and predicting their optimization, are discussed. Abstract Electrochemical energy storage (EES) devices have attracted immense research interests as an effective technology for utilizing renewable energy. 1D carbon‐based nanostructures are recognized as highly promising materials for EES application, combining the advantages of functional 1D nanostructures and carbon nanomaterials. Here, the recent advances of 1D carbon‐based nanomaterials for electrochemical storage devices are considered. First, the different categories of 1D carbon‐based nanocomposites, namely, 1D carbon‐embedded, carbon‐coated, carbon‐encapsulated, and carbon‐supported nanostructures, and the different synthesis methods are described. Next, the practical applications and optimization effects in electrochemical energy storage devices including Li‐ion batteries, Na‐ion batteries, Li–S batteries, and supercapacitors are presented. After that, the advanced in situ detection techniques that can be used to investigate the fundamental mechanisms and predict optimization of 1D carbon‐based nanocomposites are discussed. Finally, an outlook for the development trend of 1D carbon‐based nanocomposites for EES is provided.

2D Crystal–Based Fibers: Status and Challenges

By Si Meng, Tiantian Kong, Wujun Ma, Huide Wang, Han Zhang from Wiley: Small: Table of Contents. Published on Aug 13, 2019.

2D crystal–based fibers are flexible and knittable, and they have great potential for smart wearables. A review of the research status of 2D crystal–based fibers and a summary of their preparation methods are presented. This Review is helpful for developing new varieties of 2D crystal–based fibers and realizing their applications such as wearable electronics. Abstract 2D crystals are emerging new materials in multidisciplinary fields including condensed state physics, electronics, energy, environmental engineering, and biomedicine. To employ 2D crystals for practical applications, these nanoscale crystals need to be processed into macroscale materials, such as suspensions, fibers, films, and 3D macrostructures. Among these macromaterials, fibers are flexible, knittable, and easy to use, which can fully reflect the advantages of the structure and properties of 2D crystals. Therefore, the fabrication and application of 2D crystal–based fibers is of great importance for expanding the impact of 2D crystals. In this Review, 2D crystals that are successfully prepared are overviewed based on their composition of elements. Subsequently, methods for preparing 2D crystals, 2D crystals dispersions, and 2D crystal–based fibers are systematically introduced. Then, the applications of 2D crystal–based fibers, such as flexible electronic devices, high‐efficiency catalysis, and adsorption, are also discussed. Finally, the status‐of‐quo, perspectives, and future challenges of 2D crystal–based fibers are summarized. This Review provides directions and guidelines for developing new 2D crystal–based fibers and exploring their potentials in the fields of smart wearable devices.

Enhanced In Vivo Delivery of Stem Cells using Microporous Annealed Particle Scaffolds

By Jaekyung Koh, Donald R. Griffin, Maani M. Archang, An‐Chieh Feng, Thomas Horn, Michael Margolis, David Zalazar, Tatiana Segura, Philip O. Scumpia, Dino Carlo from Wiley: Small: Table of Contents. Published on Aug 13, 2019.

Void‐forming hydrogels for cell delivery must be made in advance with cells being added into the scaffold during the manufacturing process. Here, mesenchymal stem cells are co‐injected locally with microparticle scaffolds that assemble in situ immediately following injection. This approach enhances MSC retention subcutaneously when compared to cell delivery alone or delivery within traditional in situ cross‐linked nanoporous hydrogels. Abstract Delivery to the proper tissue compartment is a major obstacle hampering the potential of cellular therapeutics for medical conditions. Delivery of cells within biomaterials may improve localization, but traditional and newer void‐forming hydrogels must be made in advance with cells being added into the scaffold during the manufacturing process. Injectable, in situ cross‐linking microporous scaffolds are recently developed that demonstrate a remarkable ability to provide a matrix for cellular proliferation and growth in vitro in three dimensions. The ability of these scaffolds to deliver cells in vivo is currently unknown. Herein, it is shown that mesenchymal stem cells (MSCs) can be co‐injected locally with microparticle scaffolds assembled in situ immediately following injection. MSC delivery within a microporous scaffold enhances MSC retention subcutaneously when compared to cell delivery alone or delivery within traditional in situ cross‐linked nanoporous hydrogels. After two weeks, endothelial cells forming blood vessels are recruited to the scaffold and cells retaining the MSC marker CD29 remain viable within the scaffold. These findings highlight the utility of this approach in achieving localized delivery of stem cells through an injectable porous matrix while limiting obstacles of introducing cells within the scaffold manufacturing process.

Ni‐Catalyzed Conversion of Enol Triflates to Alkenyl Halides

By Julie Lynn Hofstra, Kelsey E Poremba, Alex Shimozono, Sarah E. Reisman from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 13, 2019.

A Ni‐catalyzed halogenation of enol triflates was developed that enables the synthesis of a broad range of alkenyl iodides, bromides, and chlorides under mild reaction conditions. The reaction utilizes inexpensive, bench stable Ni(OAc)2·4H2O as a pre‐catalyst and proceeds at room temperature in the presence of sub‐stoichiometric Zn and either cod or DMAP.

Lasing from Mechanically Exfoliated 2D Homologous Ruddlesden–Popper Perovskite Engineered by Inorganic Layer Thickness

By Yin Liang, Qiuyu Shang, Qi Wei, Liyun Zhao, Zhen Liu, Jia Shi, Yangguang Zhong, Jie Chen, Yan Gao, Meili Li, Xinfeng Liu, Guichuan Xing, Qing Zhang from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

Lasing and loss dynamics of mechanically exfoliated, homologous 2D Ruddlesden–Popper perovskite (RPP, (C4H9NH3)2(CH3NH3)n−1PbnI3n+1) crystals are reported. The Auger recombination and the electron–phonon coupling are the major loss channels, and they increase with the decreasing of inorganic layer thickness (n), leading to larger threshold in smaller‐n RPPs, and even the absence of lasing action for n

Reversible and Irreversible Modulation of Tubulin Self‐Assembly by Intense Nanosecond Pulsed Electric Fields

By Djamel Eddine Chafai, Vadym Sulimenko, Daniel Havelka, Lucie Kubínová, Pavel Dráber, Michal Cifra from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

A modulation strategy of tubulin self‐assembly in a controllable fashion is proposed. The conformation of tubulin subunits is engineered by nanosecond electropulses. The formed structures are tightly linked to the degree of conformational changes induced by nanosecond electropulses. This strategy opens a new way for the control of self‐assembly in biomolecules as well as in bioinspired materials. Abstract Tubulin self‐assembly into microtubules is a fascinating natural phenomenon. Its importance is not just crucial for functional and structural biological processes, but it also serves as an inspiration for synthetic nanomaterial innovations. The modulation of the tubulin self‐assembly process without introducing additional chemical inhibitors/promoters or stabilizers has remained an elusive process. This work reports a versatile and vigorous strategy for controlling tubulin self‐assembly by nanosecond electropulses (nsEPs). The polymerization assessed by turbidimetry is dependent on nsEPs dosage. The kinetics of microtubules formation is tightly linked to the nsEPs effects on structural properties of tubulin, and tubulin‐solvent interface, assessed by autofluorescence, and the zeta potential. Moreover, the overall size of tubulin assessed by dynamic light scattering is affected as well. Additionally, atomic force microscopy imaging reveals the formation of different assemblies reflecting applied nsEPs. It is suggested that changes in C‐terminal modification states alter tubulin polymerization‐competent conformations. Although the assembled tubulin preserve their integral structure, they might exhibit a broad range of new properties important for their functions. Thus, these transient conformation changes of tubulin and their collective properties can result in new applications.

Photo‐switchable phase separation and oligonucleotide trafficking in DNA coacervate micro‐droplets

By Nicolas Martin, Liangfei Tian, Dan Spencer, Angélique Coutable-Pennarun, J. L. Ross Anderson, Stephen Mann from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 13, 2019.

Coacervate micro‐droplets produced by liquid‐liquid phase separation have been used as synthetic protocells that mimic the dynamical organization of membrane‐free organelles in living systems. Achieving spatiotemporal control over droplet condensation and disassembly remains challenging. Herein, we describe the formation and photo‐switchable behaviour of light‐responsive coacervate droplets prepared from mixtures of double‐stranded DNA and an azobenzene cation. The droplets disassemble and reassemble under UV and blue light, respectively, due to azobenzene trans/cis photo‐isomerisation. Sequestration and release of captured oligonucleotides follows the dynamics of phase separation such that light‐activated transfer, mixing, hybridization and trafficking of the oligonucleotides can be controlled in binary populations of the droplets. Our results open perspectives for the spatiotemporal control of DNA coacervates and provide a step towards the dynamic regulation of synthetic protocells.

Copper‐mediated selenazolidine deprotection enables one‐pot chemical synthesis of challenging proteins

By Zhenguang Zhao, Norman Metanis from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 13, 2019.

While chemical protein synthesis (CPS) has granted access to challenging proteins, synthesis of longer proteins is often limited by low abundance or non‐strategic placement of cysteine (Cys) residues, essential for native chemical ligations (NCL), as well as multiple purification and isolation steps. Selective deselenization and one‐pot CPS serve as key technologies to circumvent these issues. Herein, we describe the one‐pot total synthesis of human thiosulfate: glutathione sulfurtransferase (TSTD1), a 115‐residue protein with a single Cys residue at its active site, and its seleno‐analogue. WT‐TSTD1 was synthesized in a C‐to‐N synthetic approach employing multiple NCL reactions, Cu(II)‐mediated deprotection of selenazolidine (Sez), and chemoselective deselenization, all in one‐pot. In addition, the protein’s seleno‐analogue (Se‐TSTD1), in which the active site Cys is replaced with selenocysteine, was synthesized with a kinetically controlled ligation in a one‐pot, N‐to‐C synthetic approach. TSTD1’s one‐pot synthesis was made possible by the newly reported, rapid, and facile copper‐mediated selenazolidine deprotection that can be accomplished in one minute. Finally, catalytic activity of the two proteins indicated that Se‐TSTD1 possessed only four‐fold lower activity than WT‐TSTD1 as a thiosulfate: glutathione sulfurtransferase, suggesting that selenoproteins can have physiologically comparable sulfutransferase activity as their cysteine counterparts.

Thu 12 Sep 14:00: An analysis of the threats of the consumer spyware industry

From All Talks (aka the CURE list). Published on Aug 13, 2019.

An analysis of the threats of the consumer spyware industry

Invasive surveillance software known as “spyware” is available for general consumption, allowing everyday users the ability to place a smartphone under close surveillance. The widespread availability of spyware creates clear risks that this software can be used abusively, with many indicators that it is being used frequently in the context of domestic and family violence. This presentation reports on the findings of an Australian-based study into the threats of the consumer spyware industry. The consumer spyware industry was subjected to a market analysis and legal analysis, in addition to user analysis of spyware products and a technical analysis of a select sample of spyware. Our investigation revealed a range of concerning findings about the threat of spyware, including (a) multiple spyware companies encourage and promote the use of spyware against intimate partners and children; (b) Android users carry a higher risk of being subject to spyware than iPhone users; (c) Technical analysis of spyware reveals that software developed within the consumer spyware industry often exhibits extremely poor data security practices, creating additional risks for the exposure of highly sensitive personal information and data. Ways of countering the threats of consumer spyware are considered.

Bio: Dr Diarmaid Harkin is an Alfred Deakin Postdoctoral Research Fellow and Senior Lecturer in Criminology at Deakin University. His current active research interests include the use of private security companies in the context of domestic violence, the consumer spyware industry, and the challenges of cyber-policing.

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Building a Bridge from Papermaking to Solar Fuels

By Zaiyong Jiang, Xinhan Zhang, Wei Sun, Deren Yang, Paul N. Duchesne, Yugang Gao, Zeyan Wang, Tingjiang Yan, Zhimin Yuan, Guihua Yang, Xingxiang Ji, Jiachuan Chen, Baibiao Huang, Geoffrey A. Ozin from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 13, 2019.

Black liquor, an industrial waste product of papermaking, is primarily used as a low‐grade combustible energy source. Despite its high lignin content, the potential utility of black liquor as a feedstock in products manufacturing, remains to be exploited. Demonstrated here in is the use of black liquor as a primary feed‐stock for synthesizing graphene quantum dots that exhibit both up‐conversion and photoluminescence when excited using visible/near‐infrared radiation, thereby enabling the photosensitization of ultraviolet‐absorbing TiO2 nanosheets. In addition, these graphene quantum dots can trap photo‐generated electrons to realize the effective separation of electron‐hole pairs. Together, these two processes facilitate the solar‐powered generation of H2 from H2O, and CO from H2O‐CO2, using broadband solar radiation.

A Metallaphotoredox Strategy for the Cross‐Electrophile Coupling of Alpha‐Chloro Carbonyls with Aryl Halides

By Tiffany Q. Chen, David William Cross MacMillan from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 13, 2019.

Here, we demonstrate that a metallaphotoredox‐catalyzed cross‐electrophile coupling mechanism provides a unified method for the alpha‐arylation of diverse activated alkyl chlorides, including alpha‐chloroketones, alpha‐chloroesters, alpha‐chloroamides, alpha‐chlorocarboxylic acids, and benzylic chlorides. This strategy, which is effective for a wide range of aryl bromide coupling partners, is predicated upon a halogen atom abstraction/nickel radical‐capture mechanism that is generically successful across an extensive range of carbonyl substrates. The construction and use of arylacetic acid products have further enabled two‐step protocols for the delivery of valuable building blocks for medicinal chemistry, such as aryldifluoromethyl and diarylmethane motifs.

Nanoemulsion with Porphyrin Shell for Cancer Theranostics

By Wenxiu Hou, Jenny Lou, Jiachuan Bu, Enling Chang, Lili Ding, Michael Valic, Han Ho Jeon, Danielle Charron, Catherine Coolens, Daxiang Cui, Juan Chen, Gang Zheng from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 13, 2019.

A nanoemulsion with a porphyrin shell (NewPS) is created by the self‐assembly of porphyrin salt around an oil core. The NewPS has ~100 nm spherical structure with excellent colloidal stability against radical changes in temperature, mechanical agitation, pH and in serum. The NewPS system is amenable to different porphyrin salts (mono‐sodium or tris‐sodium salt) and oils (low or high density), and is capable of co‐loading with chemotherapeutics (paclitaxel). The porphyrin salt shell is essential for the nanostructure construction and enables porphyrin‐dependent optical tunability. NewPS consisting of pyropheophorbide a mono‐salt (PyroNewPS) has an ordered J‐aggregates of porphyrin shell, which produced a narrow, red‐shifted (from 671nm to 715nm) Q‐band with increased absorbance. Upon nanostructure dissociation, fluorescence and photodynamic reactivity of porphyrin monomers are restored. As a result of the spectrally distinct photoacoustic imaging (at 715nm by intact NewPS) and fluorescence increase (at 671nm by dissociated NewPS), we could track NewPS accumulation and disruption in mice bearing KB tumors to guide effective photodynamic therapy. Substituting the oil core with lipiodol® affords additional CT contrast, whereas loading paclitaxel into NewPS facilitates drug delivery. This simple two‐component NewPS offers a new nanoplatform for multimodal cancer imaging, phototherapy and image‐guided drug delivery.

Space‐Confined Growth of Individual Wide Bandgap Single Crystal CsPbCl3 Microplatelet for Near‐Ultraviolet Photodetection

By Pengbin Gui, Hai Zhou, Fang Yao, Zehao Song, Borui Li, Guojia Fang from Wiley: Small: Table of Contents. Published on Aug 13, 2019.

A simple space‐confined growth method is introduced to synthesize high‐quality all‐inorganic wide bandgap single crystal CsPbCl3 microplatelets (MPs) at low temperature. This method overcomes the poor solubility of the precursor and obtains high‐crystallinity CsPbCl3 MPs. The as‐synthesized individual CsPbCl3 MP is introduced into a photodetector with high near‐ultraviolet photodetection performance and excellent high‐temperature thermal stability. Abstract Perovskite photodetectors (PDs) with tunable detection wavelength have attracted extensive attention due to the potential application in the field of imaging, machine vision, and artificial intelligence. Most of the perovskite PDs focus on I‐ or Br‐based materials due to their easy preparation techniques. However, their main photodetection capacity is situated in the visible region because of their narrower bandgap. Cl‐based wide bandgap perovskites, such as CsPbCl3, are scarcely reported because of the bad film quality of the spin‐coated Cl‐based perovskite, due to the poor solubility of the precursor. Therefore, ultraviolet detection using high‐quality full inorganic perovskite films, especially with high thermal stability of materials and devices, is still a big challenge. In this work, high‐quality single crystal CsPbCl3 microplatelets (MPs) synthesized by a simple space‐confined growth method at low temperature for near‐ultraviolet (NUV) PDs are reported. The single CsPbCl3 MP PDs demonstrate a decent response to NUV light with a high on/off ratio of 5.6 × 103 and a responsivity of 0.45 A W−1 at 5 V. In addition, the dark current is as low as pA level, leading to detectivity up to 1011 Jones. Moreover, PDs possess good stability and repeatability.

Thu 28 Nov 14:30: Generalised Knight Tours

From All Talks (aka the CURE list). Published on Aug 13, 2019.

Generalised Knight Tours

The classical knight tour problem extends naturally to generalised knights, which move by leaping $p$ units along one coordinate axis and $q$ units along the other. We require that $p + q$ is odd and that $p$ and $q$ are coprime, as otherwise the generalised knight cannot reach every cell. A well-known conjecture is that every generalised knight has a Hamiltonian cycle on some rectangular chessboard. We prove this conjecture. We also determine the smallest square chessboard with this property, whose side-length was first conjectured to be $2(p + q)$ by T. H. Willcocks in 1976.

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Myocardial‐Infarction‐Responsive Smart Hydrogels Targeting Matrix Metalloproteinase for On‐Demand Growth Factor Delivery

By Caixia Fan, Jiajia Shi, Yan Zhuang, Lulu Zhang, Lei Huang, Wen Yang, Bing Chen, Yanyan Chen, Zhifeng Xiao, He Shen, Yannan Zhao, Jianwu Dai from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

A matrix metalloproteinase (MMP)‐responsive hydrogel is designed to achieve on‐demand basic fibroblast growth factor release at the site of a myocardial infarct for increasing the local protein concentration and reducing unnecessary diffusion, and competitive inhibition of MMP enzymatic activity for reducing adverse myocardial remodeling. Myocardial injection of the MMP‐responsive hydrogel results in significantly improved cardiac function, increased vascularization, and ameliorated cardiac remodeling, with good clinical application prospects. Abstract Although in situ restoration of blood supply to the infarction region and attenuating pre‐existing extracellular matrix degradation remain potential therapeutic approaches for myocardial infarction (MI), local delivery of therapeutics has been limited by low accumulation (inefficacy) and unnecessary diffusion (toxicity). Here, a dual functional MI‐responsive hydrogel is fabricated for on‐demand drug delivery to promote angiogenesis and inhibit cardiac remodeling by targeting upregulated matrix metalloproteinase‐2/9 (MMP‐2/9) after MI. A glutathione (GSH)‐modified collagen hydrogel (collagen‐GSH) is prepared by conjugating collagen amine groups with GSH sulfhydryl groups and the recombinant protein GST‐TIMP‐bFGF (bFGF: basic fibroblast growth factor) by fusing bFGF with glutathione‐S‐transferase (GST) and MMP‐2/9 cleavable peptide PLGLAG (TIMP). Specific binding between GST and GSH significantly improves the amount of GST‐TIMP‐bFGF loaded in collagen‐GSH hydrogel. The TIMP peptide enclosed between GST and bFGF responds to MMPs for on‐demand release during MI. Additionally, the TIMP peptide is a competitive substrate of MMPs that inhibits the excessive degradation of cardiac matrix by MMPs after MI. GST‐TIMP‐bFGF/collagen‐GSH hydrogels promote the recovery of MI rats by enhancing vascularization and ameliorating myocardium remodeling. The results suggest that on‐demand growth factor delivery by synchronously controlling binding and responsive release to promote angiogenesis and attenuate cardiac remodeling might be promising for the treatment of ischemic heart disease.

Multifunctional Nanocomposites with High Strength and Capacitance Using 2D MXene and 1D Nanocellulose

By Weiqian Tian, Armin VahidMohammadi, Michael S. Reid, Zhen Wang, Liangqi Ouyang, Johan Erlandsson, Torbjörn Pettersson, Lars Wågberg, Majid Beidaghi, Mahiar M. Hamedi from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

Freestanding multifunctional nanocomposites are assembled from a stable and patternable hybrid dispersion of one‐dimensional cellulose nanofibrils and two‐dimensional titanium carbide MXene, with excellent integration of high conductivity (295 S cm−1), high mechanical strength (341 MPa), and high capacitance (298 F g−1). Abstract The family of two‐dimensional (2D) metal carbides and nitrides, known as MXenes, are among the most promising electrode materials for supercapacitors thanks to their high metal‐like electrical conductivity and surface‐functional‐group‐enabled pseudocapacitance. A major drawback of these materials is, however, the low mechanical strength, which prevents their applications in lightweight, flexible electronics. A strategy of assembling freestanding and mechanically robust MXene (Ti3C2Tx ) nanocomposites with one‐dimensional (1D) cellulose nanofibrils (CNFs) from their stable colloidal dispersions is reported. The high aspect ratio of CNF (width of ≈3.5 nm and length reaching tens of micrometers) and their special interactions with MXene enable nanocomposites with high mechanical strength without sacrificing electrochemical performance. CNF loading up to 20%, for example, shows a remarkably high mechanical strength of 341 MPa (an order of magnitude higher than pristine MXene films of 29 MPa) while still maintaining a high capacitance of 298 F g−1 and a high conductivity of 295 S cm−1. It is also demonstrated that MXene/CNF hybrid dispersions can be used as inks to print flexible micro‐supercapacitors with precise dimensions. This work paves the way for fabrication of robust multifunctional MXene nanocomposites for printed and lightweight structural devices.

Semitransparent Perovskite Solar Cells: From Materials and Devices to Applications

By Biao Shi, Linrui Duan, Ying Zhao, Jingshan Luo, Xiaodan Zhang from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

Semi‐transparent perovskite solar cells (ST‐PSCs) have received great attention due to their promising applications in many areas, such as building integrated photovoltaics (BIPV), tandem devices, and wearable electronics. A general overview of recent advances in ST‐PSCs from materials and devices to applications is provided, and presented alongside some personal perspectives on their future development. Abstract Semitransparent solar cells (ST‐SCs) have received great attention due to their promising application in many areas, such as building integrated photovoltaics (BIPVs), tandem devices, and wearable electronics. In the past decade, perovskite solar cells (PSCs) have revolutionized the field of photovoltaics (PVs) with their high efficiencies and facile preparation processes. Due to their large absorption coefficient and bandgap tunability, perovskites offer new opportunities to ST‐SCs. Here, a general overview is provided on the recent advances in ST‐PSCs from materials and devices to applications and some personal perspectives on the future development of ST‐PSCs.

Material‐Based Approaches for the Fabrication of Stretchable Electronics

By Dong Chan Kim, Hyung Joon Shim, Woongchan Lee, Ja Hoon Koo, Dae‐Hyeong Kim from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

The latest research developments and progress regarding material‐based approaches for the fabrication of stretchable electronics are comprehensively reviewed. Detailed descriptions of various stretchable conducting/semiconducting composites are given, along with their electrical/mechanical properties, material processing strategies, and examples of device applications. In addition, the outlook for future research in this field is discussed. Abstract Stretchable electronics are mechanically compatible with a variety of objects, especially with the soft curvilinear contours of the human body, enabling human‐friendly electronics applications that could not be achieved with conventional rigid electronics. Therefore, extensive research effort has been devoted to the development of stretchable electronics, from research on materials and unit device, to fully integrated systems. In particular, material‐processing technologies that encompass the synthesis, assembly, and patterning of intrinsically stretchable electronic materials have been actively investigated and have provided many notable breakthroughs for the advancement of stretchable electronics. Here, the latest studies of such material‐based approaches are reviewed, mainly focusing on intrinsically stretchable electronic nanocomposites that generally consist of conducting/semiconducting filler materials inside or on elastomer backbone matrices. Various approaches for fabricating these intrinsically stretchable electronic materials are presented, including the blending of electronic fillers into elastomer matrices, the formation of bi‐layered heterogeneous electronic‐layer and elastomer support‐layer structures, and modifications to polymeric molecular structures in order to impart stretchability. Detailed descriptions of the various conducting/semiconducting composites prepared by each method are provided, along with their electrical/mechanical properties and examples of device applications. To conclude, a brief future outlook is presented.

Stereoelectronic Effects in Ligand Design: Enantioselective Rhodium‐Catalyzed Hydrogenation of Aliphatic Cyclic Tetrasubstituted Enamides and Concise Synthesis of (R)‐Tofacitinib

By Chengxi Li, Feng Wan, Yuan Chen, Henian Peng, Wenjun Tang, Shu Yu, J. Christopher McWilliams, Jason Mustakis, Lacey Samp, Robert J. Maguire from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 13, 2019.

The conformationally defined, electron‐rich, C2‐symmetric, P‐chiral ligand ArcPhos was designed by taking advantage of stereoelectronic effects. With the Rh‐ArcPhos catalyst, excellent enantioselectivities and high turnovers were achieved in the asymmetric hydrogenation of aliphatic carbocyclic and heterocyclic tetrasubstituted enamides. Abstract We herein report the development of a conformationally defined, electron‐rich, C2‐symmetric, P‐chiral bisphosphorus ligand, ArcPhos, by taking advantage of stereoelectronic effects in ligand design. With the Rh‐ArcPhos catalyst, excellent enantioselectivities and unprecedentedly high turnovers (TON up to 10 000) were achieved in the asymmetric hydrogenation of aliphatic carbocyclic and heterocyclic tetrasubstituted enamides, to generate a series of chiral cis‐2‐alkyl‐substituted carbocyclic and heterocyclic amine derivatives in excellent enantiomeric ratios. This method also enabled an efficient and practical synthesis of the Janus kinase inhibitor (R)‐tofacitinib.

Internal Nucleophilic Catalyst Mediated Cyclisation/Ring Expansion Cascades for the Synthesis of Medium‐Sized Lactones and Lactams

By Aggie Lawer, James A. Rossi‐Ashton, Thomas C. Stephens, Bradley J. Challis, Ryan G. Epton, Jason M. Lynam, William P. Unsworth from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 13, 2019.

Two‐step process: A strategy for the synthesis of medium‐sized lactones and lactams from linear precursors is described in which an amine acts as an internal nucleophilic catalyst to facilitate a cyclisation/ring expansion cascade. This method obviates the need for high‐dilution conditions and enables medium‐sized ring biaryl scaffolds to be prepared with full control of atroposelectivity by point‐to‐axial chirality transfer. Abstract A strategy for the synthesis of medium‐sized lactones and lactams from linear precursors is described in which an amine acts as an internal nucleophilic catalyst to facilitate a novel cyclisation/ring expansion cascade sequence. This method obviates the need for the high‐dilution conditions usually associated with medium‐ring cyclisation protocols, as the reactions operate exclusively via kinetically favourable “normal”‐sized cyclic transition states. This same feature also enables biaryl‐containing medium‐sized rings to be prepared with complete atroposelectivity by point‐to‐axial chirality transfer.

2D Monoelemental Germanene Quantum Dots: Synthesis as Robust Photothermal Agents for Photonic Cancer Nanomedicine

By Jiang Ouyang, Chan Feng, Xiaoyuan Ji, Li Li, Hemanth Kiran Gutti, Na Yoon Kim, Dolev Artzi, Angel Xie, Na Kong, You‐Nian Liu, Guillermo J. Tearney, Xinbing Sui, Wei Tao, Omid C. Farokhzad from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 13, 2019.

A facile, top‐down, liquid‐exfoliation approach to produce ultra‐small germanene quantum dots (GeQDs) is presented. 2D GeQDs are robust photothermal therapeutic (PTT) agents and can be used for hyperpyrexia ablation of tumors guided by multimodal (photoacoustic, PA; NIR fluorescence, FL; photothermal, PT) imaging. Abstract As a new family member of the emerging two‐dimensional (2D) monoelemental materials (Xenes), germanene has shown promising advantages over the prototypical 2D Xenes, such as black phosphorus (BP) and graphene. However, efficient manufacture of novel germanene nanostructures is still a challenge. Herein, a simple top‐down approach for the liquid‐exfoliation of ultra‐small germanene quantum dots (GeQDs) is presented. The prepared GeQDs possess an average lateral size of about 4.5 nm and thickness of about 2.2 nm. The functionalized GeQDs were demonstrated to be robust photothermal agents (PTAs) with outstanding photothermal conversion efficacy (higher than those of graphene and BPQDs), superior stability, and excellent biocompatibility. As a proof‐of‐principle, 2D GeQDs‐based PTAs were used in fluorescence/photoacoustic/photothermal‐imaging‐guided hyperpyrexia ablation of tumors. This work could expand the application of 2D germanene to the field of photonic cancer nanomedicine.

The Unexplored World of Cycloalkene–Water Complexes: Primary and Assisting Interactions Unraveled by Experimental and Computational Spectroscopy

By Juan Wang, Lorenzo Spada, Junhua Chen, Shuang Gao, Silvia Alessandrini, Gang Feng, Cristina Puzzarini, Qian Gou, Jens‐Uwe Grabow, Vincenzo Barone from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 13, 2019.

The intermolecular interactions in cycloalkene–water adducts were computationally characterized, thus demonstrating that the primary O−H⋅⋅⋅πC=C hydrogen bond is dominated by the electrostatic interaction. A deeper investigation by means of a joint rotational spectroscopy/state‐of‐the‐art quantum chemistry approach also led to the determination of an accurate semi‐experimental equilibrium structure for the cyclopentene adduct.

Enhanced Raman Scattering by ZnO Superstructures: Synergistic Effect of Charge Transfer and Mie Resonances

By Wei Ji, Linfang Li, Wei Song, Xinnan Wang, Bing Zhao, Yukihiro Ozaki from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 13, 2019.

Supersize Mie: A remarkable enhancement of Raman scattering is achieved by submicrometer‐sized spherical ZnO superstructures by a synergistic effect of charge‐transfer and Mie resonances. Abstract A remarkable enhancement of Raman scattering is achieved by submicrometer‐sized spherical ZnO superstructures. The secondary superstructures of ZnO particles with a uniform diameter in the range of 220–490 nm was formed by aggregating ca. 13 nm primary single crystallites. By engineering the superstructure size to induce Mie resonances, leading to an electromagnetic contribution to the SERS enhancement. Meanwhile, a highly efficient charge‐transfer (CT) contribution derived from the primary structure of the ZnO nanocrystallites was able to enhance the SERS signals as well. The highest Raman enhancement factor of 105 was achieved for a non‐resonant molecule by the synergistic effect of CT and Mie resonances. The Mie resonances scattered near‐field effect investigated in the present study provides not only an important guide for designing novel SERS‐active semiconductor substrates, but also a coherent framework for modelling the electromagnetic mechanism of SERS on semiconductors.

Chemical Synthesis at Surfaces with an Atomic Precision: Taming Complexity and Perfection

By Paolo Samori, Can Wang, Lifeng Chi, Artur Ciesielski from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 13, 2019.

Scanning probe microscopies (SPM) are powerful tools to study structure and dynamics of molecules at surfaces and interfaces as well as to precisely manipulate atoms and molecules by applying external force, by inelastic electron tunneling, or by means of an electric field. The rapid development of these SPM manipulation modes made it possible to achieve a fine control over fundamental processes in physics of interfaces and on chemical reactivity, such as adsorption, diffusion, bond formation and bond dissociation with a precision at the single atom/molecule level. Their controlled use for the fabrication of atomic‐scale structures and synthesis of new – eventually uncommon ‐ molecules with programmed properties are reviewed. Opportunity and challenges towards the development of complex chemical systems are discussed, by analysing potential future impacts in nanoscience and nanotech industry.

Wed 21 Aug 12:30: Reining in T follicular helper cells in humoral immunity and T cell lymphoma Hosted by: Klaus Okkenhaug. There will be tea and coffee available at 12.15.

From All Talks (aka the CURE list). Published on Aug 13, 2019.

Reining in T follicular helper cells in humoral immunity and T cell lymphoma

Abstract not available

Hosted by: Klaus Okkenhaug. There will be tea and coffee available at 12.15.

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Thu 29 Aug 14:00: From molecular self-association to novel weapons in the fight against antimicrobial resistance

From Materials Chemistry Research Interest Group. Published on Aug 13, 2019.

From molecular self-association to novel weapons in the fight against antimicrobial resistance

Abstract not available

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Phonon‐Assisted Electro‐Optical Switches and Logic Gates Based on Semiconductor Nanostructures

By Zhengping Shan, Xuelu Hu, Xiao Wang, Qin Tan, Xin Yang, Yunyun Li, Huawei Liu, Xiaoxia Wang, Wei Huang, Xiaoli Zhu, Xiujuan Zhuang, Yu‐Jia Sun, Libo Ma, Jun Zhang, Oliver G. Schmidt, Ritesh Agarwal, Anlian Pan from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

High‐efficiency electro‐optical switches based on single CdS nanobelts that show low drive voltage, ultrahigh on/off ratio, and broad operational‐wavelength range are demonstrated. Their properties are due to unique electric‐field‐dependent phonon‐assisted optical transitions. Furthermore, functional NOT, NOR, and NAND optical logic gates are realized by designing simple but effective configuration of individual nanobelts on patterned electrodes. Abstract High‐performance nanostructured electro‐optical switches and logic gates are highly desirable as essential building blocks in integrated photonics. In contrast to silicon‐based optoelectronic devices, with their inherent indirect optical bandgap, weak light‐modulation mechanism, and sophisticated device configuration, direct‐bandgap‐semiconductor nanostructures with attractive electro‐optical properties are promising candidates for the construction of nanoscale optical switches for on‐chip photonic integrations. However, previously reported semiconductor‐nanostructure optical switches suffer from serious drawbacks such as high drive voltage, limited operation spectral range, and low modulation depth. High‐efficiency electro‐optical switches based on single CdS nanobelts with low drive voltage, ultra‐high on/off ratio, and broad operation wavelength range, properties resulting from unique electric‐field‐dependent phonon‐assisted optical transitions, are demonstrated. Furthermore, functional NOT, NOR, and NAND optical logic gates are demonstrated based on these switches. These switches and optical logic gates represent an important step toward integrated photonic circuits.

An Acidic‐Microenvironment‐Driven DNA Nanomachine Enables Specific ATP Imaging in the Extracellular Milieu of Tumor

By Zhenghan Di, Jian Zhao, Hongqian Chu, Wenting Xue, Yuliang Zhao, Lele Li from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

An intelligent DNA nanomachine for targeted imaging of extracellular ATP in the tumor microenvironment (TME) is designed. It can specifically anchor to the membrane of tumor cells in response to mild acidic TME, enabling an “off–on” fluorescence imaging of extracellular ATP in both primary and metastatic tumors with high signal‐to‐background ratio. Abstract Extracellular ATP is an emerging target for cancer treatment because it is a key messenger for shaping the tumor microenvironment (TME) and regulating tumor progression. However, it remains a great challenge to design biochemical probes for targeted imaging of extracellular ATP in the TME. A TME‐driven DNA nanomachine (Apt‐LIP) that permits spatially controlled imaging of ATP in the extracellular milieu of tumors with ultrahigh signal‐to‐background ratio is reported. It operates in response to the mild acidity in the TME with the pH (low) insertion peptide (pHLIP) module, thus allowing the specific anchoring of the structure‐switching signaling aptamer unit to the membrane of tumor cells for “off–on” fluorescence imaging of the extracellular ATP. Apt‐LIP allows for acidity driven visualization of different extracellular concentrations of exogenous ATP, as well as the monitoring of endogenous ATP release from cells. Furthermore, it is demonstrated that Apt‐LIP represents a promising platform for the specific imaging of the extracellular ATP in both primary and metastatic tumors. Ultimately, since diverse aptamers are obtained through in vitro selection, this design strategy can be further applied for precise detection of various extracellular targets in the TME.

Anisotropic Thermal Boundary Resistance across 2D Black Phosphorus: Experiment and Atomistic Modeling of Interfacial Energy Transport

By Man Li, Joon Sang Kang, Huu Duy Nguyen, Huan Wu, Toshihiro Aoki, Yongjie Hu from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

Energy transport across metal–2D material interfaces is systematically investigated and shows a highly anisotropic thermal boundary resistance (TBR). Experimental measurements and atomistic calculations of the interface thermal transport reveal detailed fundamental understanding of TBR–structure relationships. This study may open up new opportunities in the rational design and control of novel interface materials for advanced thermal management technologies. Abstract Interfacial thermal boundary resistance (TBR) plays a critical role in near‐junction thermal management of modern electronics. In particular, TBR can dominate heat dissipation and has become increasingly important due to the continuous emergence of novel nanomaterials with promising electronic and thermal applications. A highly anisotropic TBR across a prototype 2D material, i.e., black phosphorus, is reported through a crystal‐orientation‐dependent interfacial transport study. The measurements show that the metal–semiconductor TBR of the cross‐plane interfaces is 241% and 327% as high as that of the armchair and zigzag direction‐oriented interfaces, respectively. Atomistic ab initio calculations are conducted to analyze the anisotropic and temperature‐dependent TBR using density functional theory (DFT)‐derived full phonon dispersion relation and molecular dynamics simulation. The measurement and modeling work reveals that such a highly anisotropic TBR can be attributed to the intrinsic band structure and phonon spectral transmission. Furthermore, it is shown that phonon hopping between different branches is important to modulate the interfacial transport process but with directional preferences. A critical fundamental understanding of interfacial thermal transport and TBR–structure relationships is provided, which may open up new opportunities in developing advanced thermal management technology through the rational control over nanostructures and interfaces.

Realizing 22.5% External Quantum Efficiency for Solution‐Processed Thermally Activated Delayed‐Fluorescence OLEDs with Red Emission at 622 nm via a Synergistic Strategy of Molecular Engineering and Host Selection

By Weixuan Zeng, Tao Zhou, Weimin Ning, Cheng Zhong, Jiawei He, Shaolong Gong, Guohua Xie, Chuluo Yang from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

Solution‐processed red fluorescent organic light‐emitting diodes (OLEDs) with external quantum efficiencies of up to 22.5% are fabricated using a synergistic strategy of molecular engineering and host selection with thermally activated delayed‐fluorescence emitters. With this strategy, a good balance of the critical photophysical parameters is realized by effectively fine tuning the excited states of the emitters, which is verified to support the record‐high efficiency reported. Abstract Developing high‐efficiency solution‐processable thermally activated delayed‐fluorescence (TADF) emitters, especially in longer wavelength regions, is a formidable challenge. Three red TADF emitters, namely NAI_R1, NAI_R2, and NAI_R3, are developed by phenyl encapsulation and tert‐butyl substitution on a prototypical 1,8‐naphthalimide‐acridine hybrid. This design strategy not only grants these molecules high solubility, excellent thermal stability, and good film‐forming ability, but also pulls down their charge‐transfer (CT) energy levels excited states. Furthermore, dispersing these emitters into two different host materials of mCP and mCPCN finely tailors their CT‐state energy levels. More importantly, a synergistic combination of molecular engineering and host selection can effectively manipulate the competition between the radiative and nonradiative decay rates of the CT singlet states of these emitters and the reverse intersystem crossing from their triplet to singlet states. Consequently, the optimal combination of NAI_R3 emitter and mCP host successfully results in a state‐of‐the‐art external quantum efficiency (EQE) of 22.5% for solution‐processed red TADF organic light‐emitting diodes (OLEDs) with an emission peak above 620 nm. This finding demonstrates that a synergistic strategy of molecular engineering and host selection with TADF emitters could provide a new pathway for developing efficient solution‐processable TADF systems.

Rare‐Earth‐Element‐Ytterbium‐Substituted Lead‐Free Inorganic Perovskite Nanocrystals for Optoelectronic Applications

By Byung Joon Moon, Sang Jin Kim, Seungmin Lee, Aram Lee, Hyunjung Lee, Dong Su Lee, Tae‐Wook Kim, Seoung‐Ki Lee, Sukang Bae, Sang Hyun Lee from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

The rare‐earth element ytterbium (Yb) is substituted into the B site of a cubic ABX3 perovskite lattice in place of lead. The resulting CsYbI3 nanocrystals exhibit strong excitonic emission with high quantum yield and the potential for use in hybrid photodetectors as a photoactive layer. Such lead‐free CsYbI3 nanocrystals offer tremendous opportunities in optical and optoelectronic applications. Abstract Lead‐(Pb‐) halide perovskite nanocrystals (NCs) are interesting nanomaterials due to their excellent optical properties, such as narrow‐band emission, high photoluminescence (PL) efficiency, and wide color gamut. However, these NCs have several critical problems, such as the high toxicity of Pb, its tendency to accumulate in the human body, and phase instability. Although Pb‐free metal (Bi, Sn, etc.) halide perovskite NCs have recently been reported as possible alternatives, they exhibit poor optical and electrical properties as well as abundant intrinsic defect sites. For the first time, the synthesis and optical characterization of cesium ytterbium triiodide (CsYbI3) cubic perovskite NCs with highly uniform size distribution and high crystallinity using a simple hot‐injection method are reported. Strong excitation‐independent emission and high quantum yields for the prepared NCs are verified using photoluminescence measurements. Furthermore, these CsYbI3 NCs exhibit potential for use in organic–inorganic hybrid photodetectors as a photoactive layer. The as‐prepared samples exhibit clear on–off switching behavior as well as high photoresponsivity (2.4 × 103 A W−1) and external quantum efficiency (EQE, 5.8 × 105%) due to effective exciton dissociation and charge transport. These results suggest that CsYbI3 NCs offer tremendous opportunities in electronic and optoelectronic applications, such as chemical sensors, light emitting diodes (LEDs), and energy conversion and storage devices.

Efficient Delivery of Nerve Growth Factors to the Central Nervous System for Neural Regeneration

By Duo Xu, Di Wu, Meng Qin, Lina R. Nih, Chaoyong Liu, Zheng Cao, Jie Ren, Xiangjun Chen, Zhanlong He, Wenhai Yu, Jiaoqiong Guan, Suqin Duan, Fang Liu, Xiangsheng Liu, Jesse Li, Dushawn Harley, Bin Xu, Lihua Hou, Irvin S. Y. Chen, Jing Wen, Wei Chen, Sina Pourtaheri, Yunfeng Lu from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

A nanocapsule‐based strategy is developed to efficiently deliver nerve growth factor (NGF) to the central nervous system (CNS) in mice and nonhuman primates. Under pathological conditions, the delivery of NGF enables neural regeneration, tissue remodeling, and functional recovery in mice with spinal cord injury. This work opens new avenues for the treatment of CNS diseases and injuries. Abstract The central nervous system (CNS) plays a central role in the control of sensory and motor functions, and the disruption of its barriers can result in severe and debilitating neurological disorders. Neurotrophins are promising therapeutic agents for neural regeneration in the damaged CNS. However, their penetration across the blood–brain barrier remains a formidable challenge, representing a bottleneck for brain and spinal cord therapy. Herein, a nanocapsule‐based delivery system is reported that enables intravenously injected nerve growth factor (NGF) to enter the CNS in healthy mice and nonhuman primates. Under pathological conditions, the delivery of NGF enables neural regeneration, tissue remodeling, and functional recovery in mice with spinal cord injury. This technology can be utilized to deliver other neurotrophins and growth factors to the CNS, opening a new avenue for tissue engineering and the treatment of CNS disorders and neurodegenerative diseases.

Two‐Dimensional Arrays of Transition Metal Nitride Nanocrystals

By Xu Xiao, Hao Wang, Weizhai Bao, Patrick Urbankowski, Long Yang, Yao Yang, Kathleen Maleski, Linfan Cui, Simon J. L. Billinge, Guoxiu Wang, Yury Gogotsi from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

Two‐dimensional arrays of transition metal nitride nanocrystals are synthesized by using a general salt‐templating method. During ammoniation, the initially formed metal oxides are etched and topochemically transformed to metal nitrides, resulting in interconnected metal nitride nanocrystals. Such a unique structure provides both high surface area and conductivity, as demonstrated in a highly stable Li–S battery. Abstract The synthesis of low‐dimensional transition metal nitride (TMN) nanomaterials is developing rapidly, as their fundamental properties, such as high electrical conductivity, lead to many important applications. However, TMN nanostructures synthesized by traditional strategies do not allow for maximum conductivity and accessibility of active sites simultaneously, which is a crucial factor for many applications in plasmonics, energy storage, sensing, and so on. Unique interconnected two‐dimensional (2D) arrays of few‐nanometer TMN nanocrystals not only having electronic conductivity in‐plane, but also allowing transport of ions and electrolyte through the porous nanosheets, which are obtained by topochemical synthesis on the surface of a salt template, are reported. As a demonstration of their application in a lithium–sulfur battery, it is shown that 2D arrays of several nitrides can achieve a high initial capacity of >1000 mAh g−1 at 0.2 C and only about 13% degradation over 1000 cycles at 1 C under a high areal sulfur loading (>5 mg cm−2).

A 3D and Stable Lithium Anode for High‐Performance Lithium–Iodine Batteries

By Kang Li, Ziyu Hu, Jizhen Ma, Song Chen, Dexu Mu, Jintao Zhang from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

The enhanced lithiophilicity of nitrogen/phosphorous‐doped carbon cloth facilitates uniform lithium coating on carbon fibers. This enables the construction of a 3D lithium anode with superior cycling stability for enhanced lithium–iodine battery performance. Abstract Lithium metal is considered as the most promising anode material due to its high theoretical specific capacity and the low electrochemical reduction potential. However, severe dendrite problems have to be addressed for fabricating stable and rechargeable batteries (e.g., lithium–iodine batteries). To fabricate a high‐performance lithium–iodine (Li–I2) battery, a 3D stable lithium metal anode is prepared by loading of molten lithium on carbon cloth doped with nitrogen and phosphorous. Experimental observations and theoretical calculation reveal that the N,P codoping greatly improves the lithiophilicity of the carbon cloth, which not only enables the uniform loading of molten lithium but also facilitates reversible lithium stripping and plating. Dendrites formation can thus be significantly suppressed at a 3D lithium electrode, leading to stable voltage profiles over 600 h at a current density of 3 mA cm−2. A fuel cell with such an electrode and a lithium–iodine cathode shows impressive long‐term stability with a capacity retention of around 100% over 4000 cycles and enhanced high‐rate capability. These results demonstrate the promising applications of 3D stable lithium metal anodes in next‐generation rechargeable batteries.

Logic‐Based Delivery of Site‐Specifically Modified Proteins from Environmentally Responsive Hydrogel Biomaterials

By Prathamesh Milind Gawade, Jared A. Shadish, Barry A. Badeau, Cole A. DeForest from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

The programmed release of site‐specifically modified proteins from hydrogel biomaterials in response to precise combinations of environmental inputs is specified using Boolean YES/OR/AND logic. Sequential and independently controlled release of proteins from a common material is afforded through well‐defined installation of degradable moieties tethering the protein to the gel. Abstract The controlled presentation of proteins from and within materials remains of significant interest for many bioengineering applications. Though “smart” platforms offer control over protein release in response to a single external cue, no strategy has been developed to trigger delivery in response to user‐specified combinations of environmental inputs, nor to independently control the release of multiple species from a homogenous material. Here, a modular semisynthetic scheme is introduced to govern the release of site‐specifically modified proteins from hydrogels following Boolean logic. A sortase‐mediated transpeptidation reaction is used to generate recombinant proteins C‐terminally tethered to gels through environmentally sensitive degradable linkers. By varying the connectivity of multiple stimuli‐labile moieties within these customizable linkers, YES/OR/AND control of protein release is exhaustively demonstrated in response to one and two‐input combinations involving enzyme, reductant, and light. Tethering of multiple proteins each through a different stimuli‐sensitive linker permits their independent and sequential release from a common material. It is expected that these methodologies will enable new opportunities in tissue engineering and therapeutic delivery.

Self‐Supported and Flexible Sulfur Cathode Enabled via Synergistic Confinement for High‐Energy‐Density Lithium–Sulfur Batteries

By Zhuosen Wang, Jiadong Shen, Jun Liu, Xijun Xu, Zhengbo Liu, Renzong Hu, Lichun Yang, Yuezhan Feng, Jun Liu, Zhicong Shi, Liuzhang Ouyang, Yan Yu, Min Zhu from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

A flexible sulfur cathode integrating sulfur, flexible carbon cloth, and N‐doped carbon nanoarrays with embedded CoP is successfully designed. Due to the artful structure and synergistic confinement for soluble lithium polysulfides, it displays an outstanding long‐term cycling performance and an ultralow decay of 0.016% per cycle during the whole 600 cycles at 2C. Abstract Lithium–sulfur (Li–S) batteries have attracted much attention in the field of electrochemical energy storage due to their high energy density and low cost. However, the “shuttle effect” of the sulfur cathode, resulting in poor cyclic performance, is a big barrier for the development of Li–S batteries. Herein, a novel sulfur cathode integrating sulfur, flexible carbon cloth, and metal–organic framework (MOF)‐derived N‐doped carbon nanoarrays with embedded CoP (CC@CoP/C) is designed. These unique flexible nanoarrays with embedded polar CoP nanoparticles not only offer enough voids for volume expansion to maintain the structural stability during the electrochemical process, but also promote the physical encapsulation and chemical entrapment of all sulfur species. Such designed CC@CoP/C cathodes with synergistic confinement (physical adsorption and chemical interactions) for soluble intermediate lithium polysulfides possess high sulfur loadings (as high as 4.17 mg cm–2) and exhibit large specific capacities at different C‐rates. Specially, an outstanding long‐term cycling performance can be reached. For example, an ultralow decay of 0.016% per cycle during the whole 600 cycles at a high current density of 2C is displayed. The current work provides a promising design strategy for high‐energy‐density Li–S batteries.

Strong and Tough Glass with Self‐Dispersed Nanoparticles via Solidification

By Qiang‐Guo Jiang, Chezheng Cao, Ting‐Chiang Lin, Shanghua Wu, Xiaochun Li from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

A strong and tough glass can be fabricated through a direct‐solidification process using a nanoparticle self‐dispersion mechanism, delivering a 6.1% strain limit and strength close to the theoretical limit. The fracture toughness of this glass is significantly higher than any other inorganic glasses. This new method opens up remarkable opportunities for glass and ceramic research, manufacturing, and applications. Abstract Glassy materials can be broadly defined as any amorphous solid, which are important in nature and have significant societal value for their applications in daily life and industry. Although many methods have been applied, the fracture toughness of traditional glasses is still very low due to intrinsic brittleness, significantly limiting their use for structural applications. While nanoelements may be added into glasses and ceramics to form nanocomposites with enhanced properties, it is extremely difficult to distribute and disperse them inside the liquid glass/ceramic matrix with traditional processing methods. It is shown that a strong and tough glass can be fabricated through a direct‐solidification process using a nanoparticle self‐dispersion mechanism in a glass melt (2MgO·2Al2O3·5SiO2) with the assistance of B2O3, delivering a 6.1% strain limit and strength up to E/14 (E is elastic modulus), which is close to the theoretical limit of E/10 and one of the highest among all materials reported so far. The fracture toughness of the glass with 30 vol% SiC nanoparticles is significantly higher than any other inorganic glass tested under similar conditions. This new method opens up remarkable opportunities for glass and ceramic research, manufacturing, and applications.

Horizontal Growth of Lithium on Parallelly Aligned MXene Layers towards Dendrite‐Free Metallic Lithium Anodes

By Di Zhang, Shuai Wang, Bin Li, Yongji Gong, Shubin Yang from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

A dendrite‐free lithium anode with good deep striping–plating up to 35 mAh cm−2 is achieved via parallelly aligned MXene (Ti3C2Tx) layers. This not only allows the efficient guiding of lithium nucleation on the surface of the MXene nanosheets, but also facilitates the horizontal growth of lithium on the MXene layers. Abstract Although metallic lithium is an extremely promising anode for lithium‐based batteries due to its high theoretical capacity, the uncontrollable growth of lithium dendrites, in particular under deep stripping and plating, have stagnated its application. It is demonstrated that parallelly aligned MXene (Ti3C2Tx ) layers enable the efficient guiding of lithium nucleation and growth on the surface of 2D MXene nanosheets, giving rise to horizontal‐growth lithium anodes. Moreover, the inherent fluorine terminations in MXene afford a uniform and durable solid electrolyte interface with lithium fluoride at the anode/electrolyte interface, efficiently regulating electromigration of lithium ions. Thus, a dendrite‐free lithium anode with a long cycle life up to 900 h and excellent deep stripping–plating capabilities up to 35 mAh cm−2 is achieved, which can further serve as an anode for a lithium metal battery, exhibiting high cycle stability up to 1000 cycles.

Fast and Efficient CRISPR/Cas9 Genome Editing In Vivo Enabled by Bioreducible Lipid and Messenger RNA Nanoparticles

By Ji Liu, Jin Chang, Ying Jiang, Xiandi Meng, Tianmeng Sun, Lanqun Mao, Qiaobing Xu, Ming Wang from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

A bioreducible lipid nanoparticle integrated with disulfide bonds can efficiently deliver Cas9 messenger RNA (mRNA) and single‐guide RNA into cells, while releasing mRNA in response to the reductive intracellular environment for genome editing as fast as 24 h post mRNA delivery. The leading lipid nanoparticle, BAMEA‐O16B, represents one of the most efficient CRISPR/Cas9 delivery nanocarriers reported so far. Abstract A main challenge to broaden the biomedical application of CRISPR/Cas9 (clustered regularly interspaced short palindromic repeat (CRISPR) associated protein 9) genome editing technique is the delivery of Cas9 nuclease and single‐guide RNA (sgRNA) into the specific cell and organ. An effective and very fast CRISPR/Cas9 genome editing in vitro and in vivo enabled by bioreducible lipid/Cas9 messenger RNA (mRNA) nanoparticle is reported. BAMEA‐O16B, a lipid nanoparticle integrated with disulfide bonds, can efficiently deliver Cas9 mRNA and sgRNA into cells while releasing RNA in response to the reductive intracellular environment for genome editing as fast as 24 h post mRNA delivery. It is demonstrated that the simultaneous delivery of Cas9 mRNA and sgRNA using BAMEA‐O16B knocks out green fluorescent protein (GFP) expression of human embryonic kidney cells with efficiency up to 90%. Moreover, the intravenous injection of BAMEA‐O16B/Cas9 mRNA/sgRNA nanoparticle effectively accumulates in hepatocytes, and knocks down proprotein convertase subtilisin/kexin type 9 level in mouse serum down to 20% of nontreatment. The leading lipid nanoparticle, BAMEA‐O16B, represents one of the most efficient CRISPR/Cas9 delivery nanocarriers reported so far, and it can broaden the therapeutic promise of mRNA and CRISPR/Cas9 technique further.

Additive Manufacturing of 3D‐Architected Multifunctional Metal Oxides

By Daryl W. Yee, Max L. Lifson, Bryce W. Edwards, Julia R. Greer from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

Fabrication of 3D nanoarchitected multifunctional metal oxides is performed through a facile method using a metal‐ion‐containing aqueous photoresin, which is polymerized using two‐photon lithography and calcined to give the metal oxide structure. Zinc oxide microstructures, with sub‐micrometer features, fabricated using this technique exhibit an electromechanical response that could enable the production of previously impossible 3D smart devices. Abstract Additive manufacturing (AM) of complex three‐dimensional (3D) metal oxides at the micro‐ and nanoscales has attracted considerable attention in recent years. State‐of‐the‐art techniques that use slurry‐based or organic–inorganic photoresins are often hampered by challenges in resin preparation and synthesis, and/or by the limited resolution of patterned features. A facile process for fabricating 3D‐architected metal oxides via the use of an aqueous metal‐ion‐containing photoresin is presented. The efficacy of this process, which is termed photopolymer complex synthesis, is demonstrated by creating nanoarchitected zinc oxide (ZnO) architectures with feature sizes of 250 nm, by first patterning a zinc‐ion‐containing aqueous photoresin using two‐photon lithography and subsequently calcining them at 500 ºC. Transmission electron microscopy (TEM) analysis reveals their microstructure to be nanocrystalline ZnO with grain sizes of 5.1 ± 1.6 nm. In situ compression experiments conducted in a scanning electron microscope show an emergent electromechanical response: a 200 nm mechanical compression of an architected ZnO structure results in a voltage drop of 0.52 mV. This photopolymer complex synthesis provides a pathway to easily create arbitrarily shaped 3D metal oxides that could enable previously impossible devices and smart materials.

An All‐Organic Semiconductor C3N4/PDINH Heterostructure with Advanced Antibacterial Photocatalytic Therapy Activity

By Longwei Wang, Xiao Zhang, Xin Yu, Fene Gao, Ziyi Shen, Xiaolei Zhang, Shenguang Ge, Jing Liu, Zhanjun Gu, Chunying Chen from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

An all‐organic metal‐free semiconductor C3N4/PDINH heterostructure with advanced antibacterial photocatalytic therapy activity is demonstrated. The formation of the heterostructure can extend the spectrum utilization range to 750 nm, which produces more ROS under light illumination and acts on bacteria‐infected skin. This eliminates the inflammation of the affected area and enables wounds to be cured quickly. Abstract Antibacterial photocatalytic therapy has been reported as a promising alternative water disinfection technology for combating antibiotic‐resistant bacteria. Numerous inorganic nanosystems have been developed as antibiotic replacements for bacterial infection treatment, but these are limited due to the toxicity risk of heavy metal species. Organic semiconductor photocatalytic materials have attracted great attention due to their good biocompatibility, chemically tunable electronic structure, diverse structural flexibility, suitable band gap, low cost, and the abundance of the resources they require. An all‐organic composite photocatalytic nanomaterial C3N4/perylene‐3,4,9,10‐tetracarboxylic diimide (PDINH) heterostructure is created through recrystallization of PDINH on the surface of C3N4 in situ, resulting in enhanced photocatalytic efficiency due to the formation of a basal heterostructure. The absorption spectrum of this composite structure can be extended from ultraviolet to near‐infrared light (750 nm), enhancing the photocatalytic effect to produce more reactive oxygen species, which have an excellent inactivation effect on both Gram‐negative and positive bacteria, while demonstrating negligible toxicity to normal tissue cells. An efficient promotion of infectious wound regeneration in mice with Staphylococcus aureus infected dermal wounds is demonstrated. This all‐organic heterostructure shows great promise for use in wound disinfection.

Lead Selenide (PbSe) Colloidal Quantum Dot Solar Cells with >10% Efficiency

By Waqar Ahmad, Jungang He, Zhitian Liu, Ke Xu, Zhuang Chen, Xiaokun Yang, Dengbing Li, Yong Xia, Jianbing Zhang, Chao Chen from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

Highly air‐stable PbSe colloidal quantum dots (CQDs) are produced via an in situ chloride and cadmium passivation technique. A high‐quality film is fabricated using solution‐phase ligand exchange and a one‐step deposition method. By using a PbS‐EDT (EDT = 1,2‐ethanedithiol) hole‐transporting layer, a PbI2‐capped PbSe‐CQD‐based photovoltaic device shows a record efficiency of 10.68% with impressive air and light soaking stability. Abstract Low‐cost solution‐processed lead chalcogenide colloidal quantum dots (CQDs) have garnered great attention in photovoltaic (PV) applications. In particular, lead selenide (PbSe) CQDs are regarded as attractive active absorbers in solar cells due to their high multiple‐exciton generation and large exciton Bohr radius. However, their low air stability and occurrence of traps/defects during film formation restrict their further development. Air‐stable PbSe CQDs are first synthesized through a cation exchange technique, followed by a solution‐phase ligand exchange approach, and finally absorber films are prepared using a one‐step spin‐coating method. The best PV device fabricated using PbSe CQD inks exhibits a reproducible power conversion efficiency of 10.68%, 16% higher than the previous efficiency record (9.2%). Moreover, the device displays remarkably 40‐day storage and 8 h illuminating stability. This novel strategy could provide an alternative route toward the use of PbSe CQDs in low‐cost and high‐performance infrared optoelectronic devices, such as infrared photodetectors and multijunction solar cells.

Fabrication of Lamellar Nanosphere Structure for Effective Stress‐Management in Large‐Volume‐Variation Anodes of High‐Energy Lithium‐Ion Batteries

By Jaekyung Sung, Jiyoung Ma, Seong‐Hyeon Choi, Jaehyung Hong, Namhyung Kim, Sujong Chae, Yeonguk Son, Sung Youb Kim, Jaephil Cho from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

A SiOx‐interlayer within a nanosphere anode, synthesized via a one‐pot chemical vapor deposition (CVD) method, enhances the cyclability of the Li‐ion battery system by sustaining its morphological integrity through mitigating stress intensification. Tested under industrial protocols, this anode exhibits a 1.7 times higher average energy density than conventional graphite. This breakthrough technology sheds light on the practical implementation of large‐volume‐change anodes. Abstract The use of high‐capacity anode materials to overcome the energy density limits imposed by the utilization of low‐theoretical‐capacity conventional graphite has recently drawn increased attention. Until now, stress management (including strategies relying on size, surface coating, and free volume control) has been achieved by addressing the critical problems originating from significant anode volume expansion upon lithiation. However, commercially viable alternatives to graphite have not yet been found. A new stress‐management strategy relying on the use of a lamellar nanosphere Si anode is proposed. Specifically, nanospheres comprising ≈50 nm Si nanoparticles encapsulated by SiOx /Si/SiOx /C layers with thicknesses of

Perovskite Bifunctional Device with Improved Electroluminescent and Photovoltaic Performance through Interfacial Energy‐Band Engineering

By Jiangsheng Xie, Pengjie Hang, Han Wang, Shenghe Zhao, Ge Li, Yanjun Fang, Feng Liu, Xinlu Guo, Hepeng Zhu, Xinhui Lu, Xuegong Yu, Christopher C. S. Chan, Kam Sing Wong, Deren Yang, Jianbin Xu, Keyou Yan from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

A type of perovskite bifunctional device (PBD) with high photovoltaic (PV) and electroluminescence (EL) performance is developed. Interfacial energy‐band engineering between the perovskite and hole‐transport layer (HTL) is performed to turn the n‐type surface of the perovskite into p‐type and also correct the misalignment to form a well‐defined n–i–p heterojunction. Abstract Currently, photovoltaic/electroluminescent (PV/EL) perovskite bifunctional devices (PBDs) exhibit poor performance due to defects and interfacial misalignment of the energy band. Interfacial energy‐band engineering between the perovskite and hole‐transport layer (HTL) is introduced to reduce energy loss, through adding corrosion‐free 3,3′‐(2,7‐dibromo‐9H‐fluorene‐9,9‐diyl) bis(n,n‐dimethylpropan‐1‐amine) (FN‐Br) into a HTL free of lithium salt. This strategy can turn the n‐type surface of perovskite into p‐type and thus correct the misalignment to form a well‐defined N–I–P heterojunction. The tailored PBD achieves a high PV efficiency of up to 21.54% (certified 20.24%) and 4.3% EL external quantum efficiency. Free of destructive additives, the unencapsulated devices maintain >92% of their initial PV performance for 500 h at maximum power point under standard air mass 1.5G illumination. This strategy can serve as a general guideline to enhance PV and EL performance of perovskite devices while ensuring excellent stability.

Linear Dichroism Conversion in Quasi‐1D Perovskite Chalcogenide

By Jiangbin Wu, Xin Cong, Shanyuan Niu, Fanxin Liu, Huan Zhao, Zhonghao Du, Jayakanth Ravichandran, Ping‐Heng Tan, Han Wang from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

The linear dichroism conversion phenomenon is reported in quasi‐1D hexagonal perovskite chalcogenide BaTiS3, which also shows a record level of optical anisotropy in the visible range. Wavelength‐dependent polarization‐resolved Raman spectroscopy and first‐principles calculations further confirm the orthogonal cross‐over of the linear dichroism polarity in this material. This discovery could lead to novel photonic devices for multispectral imaging, sensing, and communication. Abstract Anisotropic photonic materials with linear dichroism are crucial components in many sensing, imaging, and communication applications. Such materials play an important role as polarizers, filters, and waveplates in photonic devices and circuits. Conventional crystalline materials with optical anisotropy typically show unidirectional linear dichroism over a broad wavelength range. The linear dichroism conversion phenomenon has not been observed in crystalline materials. The investigation of the unique linear dichroism conversion phenomenon in quasi‐1D hexagonal perovskite chalcogenide BaTiS3 is reported. This material shows a record level of optical anisotropy within the visible wavelength range. In contrast to conventional anisotropic optical materials, the linear dichroism polarity in BaTiS3 makes an orthogonal change at an optical wavelength corresponding to the photon energy of 1.78 eV. First‐principles calculations reveal that this anomalous linear dichroism conversion behavior originates from the different selection rules of the parallel energy bands in the BaTiS3 material. Wavelength‐dependent polarized Raman spectroscopy further confirms this phenomenon. Such a material, with linear dichroism conversion properties, could facilitate the sensing and control of the energy and polarization of light, and lead to novel photonic devices such as polarization‐wavelength selective detectors and lasers for multispectral imaging, sensing, and optical communication applications.

Nanostructured Back Reflectors for Efficient Colloidal Quantum‐Dot Infrared Optoelectronics

By Se‐Woong Baek, Pau Molet, Min‐Jae Choi, Margherita Biondi, Olivier Ouellette, James Fan, Sjoerd Hoogland, F. Pelayo García de Arquer, Agustín Mihi, Edward H. Sargent from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

A colloidal‐quantum‐dot (CQD) solar cell with a patterned organic hole‐transport layer responsible for efficient light trapping in the near infrared is presented. The designed nanoimprinted organic structure gives the device efficient backscattering electrodes that lead to a 22% power conversion efficiency increase, achieving power conversion efficiencies of 1.34% in the near infrared, beyond Si absorption. Abstract Colloidal quantum dots (CQDs) can be used to extend the response of solar cells, enabling the utilization of solar power that lies to the red of the bandgap of c‐Si and perovskites. To achieve largely complete absorption of infrared (IR) photons in CQD solids requires thicknesses on the micrometer range; however, this exceeds the typical diffusion lengths (≈300 nm) of photoexcited charges in these materials. Nanostructured metal back electrodes that grant the cell efficient IR light trapping in thin active layers with no deterioration of the electrical properties are demonstrated. Specifically, a new hole‐transport layer (HTL) is developed and directly nanostructured. Firstly, a material set to replace conventional rigid HTLs in CQD devices is developed with a moldable HTL that combines the mechanical and chemical requisites for nanoimprint lithography with the optoelectronic properties necessary to retain efficient charge extraction through an optically thick layer. The new HTL is nanostructured in a 2D lattice and conformally coated with MoO3/Ag. The photonic structure in the back electrode provides a record photoelectric conversion efficiency of 86%, beyond the Si bandgap, and a 22% higher IR power conversion efficiency compared to the best previous reports.

3D Helix Engineering in Chiral Photonic Materials

By Augustinus J. J. Kragt, Davey C. Hoekstra, Sjoerd Stallinga, Dirk J. Broer, Albertus P. H. J. Schenning from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

3D engineered photonic materials are of interest for emerging applications, such as anticounterfeit labels, data encryption, and super‐reflective films. 3D engineered chiral nematic‐liquid‐crystal materials, which exhibit a changing color contrast between the image and the surroundings upon changes in the polarization of incident light, are reported. Abstract Engineering the helical structure of chiral photonic materials in three dimensions remains a challenge. 3D helix engineered photonic materials are fabricated by local stratification in a photopolymerizable chiral nematic liquid crystal. The obtained chiral photonic materials reflect both handedness of circular polarized light and show super‐reflectivity. Simulations match the experimentally observed photonic properties and reveal a distorted helical structure. 3D engineered polymer films can be made that reflect both left‐ and right handed circular and linear polarized light dependent and exhibit a changing color contrast upon altering the polarization of incident light. Hence, these 3D engineered photonic materials are of interest for new and emerging applications ranging from anti‐counterfeit labels and data encryption to aesthetics and super‐reflective films.

Oxygen‐Vacancy‐Introduced BaSnO3−δ Photoanodes with Tunable Band Structures for Efficient Solar‐Driven Water Splitting

By Myeongjin Kim, Byeongyong Lee, Hyun Ju, Jin Young Kim, Jooheon Kim, Seung Woo Lee from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

The introduction of oxygen vacancies into barium stannate plays a crucial role in reducing the bandgap energy and suppressing electron–hole recombination. A simple chemical reduction method for synthesizing high‐performance photoanodes with tunable band structures is proposed. Abstract To achieve excellent photoelectrochemical water‐splitting activity, photoanode materials with high light absorption and good charge‐separation efficiency are essential. One effective strategy for the production of materials satisfying these requirements is to adjust their band structure and corresponding bandgap energy by introducing oxygen vacancies. A simple chemical reduction method that can systematically generate oxygen vacancies in barium stannate (BaSnO3 (BSO)) crystal is introduced, which thus allows for precise control of the bandgap energy. A BSO photoanode with optimum oxygen‐vacancy concentration (8.7%) exhibits high light‐absorption and good charge‐separation capabilities. After deposition of FeOOH/NiOOH oxygen evolution cocatalysts on its surface, this photoanode shows a remarkable photocurrent density of 7.32 mA cm−2 at a potential of 1.23 V versus a reversible hydrogen electrode under AM1.5G simulated sunlight. Moreover, a tandem device constructed with a perovskite solar cell exhibits an operating photocurrent density of 6.84 mA cm−2 and stable gas production with an average solar‐to‐hydrogen conversion efficiency of 7.92% for 100 h, thus functioning as an outstanding unbiased water‐splitting system.

Extrinsic Green Photoluminescence from the Edges of 2D Cesium Lead Halides

By Chong Wang, Yanan Wang, Xinghua Su, Viktor G. Hadjiev, Shenyu Dai, Zhaojun Qin, Hector A. Calderon Benavides, Yizhou Ni, Qiang Li, Jie Jian, Md. Kamrul Alam, Haiyan Wang, Francisco C. Robles Hernandez, Yan Yao, Shuo Chen, Qingkai Yu, Guoying Feng, Zhiming Wang, Jiming Bao from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

Same‐spot Raman photoluminescence with two lasers in a diamond anvil cell under hydrostatic pressure reveals that CsPbBr3 nanocrystals, mostly located on the edges of CsPb2Br5 2D platelets, are responsible for CsPb2Br5's green emission. This sensitive noninvasive technique combining static and dynamic probes establishes a one‐to‐one property–structure relationship and distinguishes light emission from point defects versus nanoinclusions. Abstract Since the first report of the green emission of 2D all‐inorganic CsPb2Br5, its bandgap and photoluminescence (PL) origin have generated intense debate and remained controversial. After the discovery that PL centers occupy only specific morphological structures in CsPb2Br5, a two‐step highly sensitive and noninvasive optical technique is employed to resolve the controversy. Same‐spot Raman‐PL as a static property–structure probe reveals that CsPbBr3 nanocrystals are contributing to the green emission of CsPb2Br5; pressure‐dependent Raman‐PL with a diamond anvil cell as a dynamic probe further rules out point defects such as Br vacancies as an alternative mechanism. Optical absorption under hydrostatic pressure shows that the bandgap of CsPb2Br5 is 0.3–0.4 eV higher than previously reported values and remains nearly constant with pressure up to 2 GPa in good agreement with full‐fledged density functional theory (DFT) calculations. Using ion exchange of Br with Cl and I, it is further proved that CsPbBr3−x Xx (X = Cl or I) is responsible for the strong visible PL in CsPb2Br5−x Xx . This experimental approach is applicable to all PL‐active materials to distinguish intrinsic defects from extrinsic nanocrystals, and the findings pave the way for new design and development of highly efficient optoelectronic devices based on all‐inorganic lead halides.

In Situ Method Correlating Raman Vibrational Characteristics to Chemical Expansion via Oxygen Nonstoichiometry of Perovskite Thin Films

By Eva Sediva, Thomas Defferriere, Nicola H. Perry, Harry L. Tuller, Jennifer L. M. Rupp from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

A new methodology for the calibration of oxygen nonstoichiometry in perovskite thin films to their oxygen vibrational modes is introduced. This is achieved by actively pumping oxygen in and out of Sr(Ti,Fe)O3−y thin films integrated into an electrochemical cell and measuring in situ Raman spectra. Abstract Effective integration of perovskite films into devices requires knowledge of their electro‐chemomechanical properties. Raman spectroscopy is an excellent tool for probing such properties as the films' vibrational characteristics couple to the lattice volumetric changes during chemical expansion. While lattice volumetric changes are typically accessed by analyzing Raman shifts as a function of pressure, stress, or temperature, such methods can be impractical for thin films and do not capture information on chemical expansion. An in situ Raman spectroscopy technique using an electrochemical titration cell to change the oxygen nonstoichiometry of a model perovskite film, Sr(Ti,Fe)O3−y , is reported and the lattice vibrational properties are correlated to the material's chemical expansion. How to select an appropriate Raman vibrational mode to track the evolution in oxygen nonstoichiometry is discussed. Subsequently, the frequency of the oxygen stretching mode around Fe4+ is tracked, as it decreases during reduction as the material expands and increases during reoxidation as the material shrinks. This methodology of oxygen pumping and in situ Raman spectroscopy of oxide films enables future in operando measurements even for small material volumes, as is typical for applications of films as electrodes or electrolytes utilized in electrochemical energy conversion or memory devices.

Self‐Sorting of 10‐µm‐Long Single‐Walled Carbon Nanotubes in Aqueous Solution

By Peng Wang, Benjamin Barnes, Xiaojian Wu, Haoran Qu, Chiyu Zhang, Yang Shi, Robert J. Headrick, Matteo Pasquali, YuHuang Wang from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

Ultralong carbon nanotubes self‐sort in a superacid–surfactant exchange process. This self‐sorting effect is driven by the length‐dependent phase behaviors of rigid rods in solution. The obtained nanotubes, with the longest approaching 13 µm, exhibit a carrier mobility as high as ≈90 cm2 V−1 s−1 in thin‐film transistors, which is ≈10 times higher than the short controls and which approaches that of polycrystalline silicon. Abstract Single‐walled carbon nanotubes (SWCNTs) are a class of 1D nanomaterials that exhibit extraordinary electrical and optical properties. However, many of their fundamental studies and practical applications are stymied by sample polydispersity. SWCNTs are synthesized in bulk with broad structural (chirality) and geometrical (length and diameter) distributions; problematically, all known post‐synthetic sorting methods rely on ultrasonication, which cuts SWCNTs into short segments (typically 10 µm) SWCNTs can be efficiently separated from shorter ones through a solution‐phase “self‐sorting”. It is shown that thin‐film transistors fabricated from long semiconducting SWCNTs exhibit a carrier mobility as high as ≈90 cm2 V−1 s−1, which is ≈10 times higher than those which use shorter counterparts and well exceeds other known materials such as organic semiconducting polymers (

Masthead: (Adv. Mater. 33/2019)

By from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

Cocktail Strategy Based on Spatio‐Temporally Controlled Nano Device Improves Therapy of Breast Cancer

By Tianqun Lang, Yiran Liu, Zhong Zheng, Wei Ran, Yihui Zhai, Qi Yin, Pengcheng Zhang, Yaping Li from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

Contents: (Adv. Mater. 33/2019)

By from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

Embolic Agents: Advances in Biomaterials and Technologies for Vascular Embolization (Adv. Mater. 33/2019)

By Jingjie Hu, Hassan Albadawi, Brian W. Chong, Amy R. Deipolyi, Rahul A. Sheth, Ali Khademhosseini, Rahmi Oklu from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

In article number 1901071, Rahmi Oklu and co‐workers give an overview of current and emerging technologies in endovascular embolization with respect to devices, materials, mechanisms, and design guidelines. In the cover image, the evolution of embolic materials is illustrated, from the 1950s, where a patient's own blood was heated to clot the blood and then reinjected, to liquid embolic agents in the 2000s, to the future, exemplified by advanced gel embolics. Image credit: S. Masoud Moosavi‐Basri, Sharif University of Technology.

Neural Regeneration: Efficient Delivery of Nerve Growth Factors to the Central Nervous System for Neural Regeneration (Adv. Mater. 33/2019)

By Duo Xu, Di Wu, Meng Qin, Lina R. Nih, Chaoyong Liu, Zheng Cao, Jie Ren, Xiangjun Chen, Zhanlong He, Wenhai Yu, Jiaoqiong Guan, Suqin Duan, Fang Liu, Xiangsheng Liu, Jesse Li, Dushawn Harley, Bin Xu, Lihua Hou, Irvin S. Y. Chen, Jing Wen, Wei Chen, Sina Pourtaheri, Yunfeng Lu from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

Neurotrophins are promising candidates for central nervous system (CNS) diseases and injuries, while their inability to enter the CNS remains a bottleneck for therapeutic purposes. In article number 1900727, Jing Wen, Wei Chen, Sina Pourtaheri, Yunfeng Lu, and co‐workers report a nanocapsule‐based delivery strategy, which enables the efficient entry of nerve growth factors (NGFs) to the CNS. In mice with spinal cord injuries, the effective delivery of NGF promotes neural regeneration, tissue remodeling, and functional recovery.

Lithium–Sulfur Batteries: Self‐Supported and Flexible Sulfur Cathode Enabled via Synergistic Confinement for High‐Energy‐Density Lithium–Sulfur Batteries (Adv. Mater. 33/2019)

By Zhuosen Wang, Jiadong Shen, Jun Liu, Xijun Xu, Zhengbo Liu, Renzong Hu, Lichun Yang, Yuezhan Feng, Jun Liu, Zhicong Shi, Liuzhang Ouyang, Yan Yu, Min Zhu from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

In article number 1902228, Jun Liu, Yan Yu, Min Zhu, and co‐workers describe the design and use of a flexible sulfur cathode integrating sulfur, flexible carbon cloth, and N‐doped carbon nanoarrays with embedded CoP for lithium–sulfur batteries. The structure and the synergistic confinement for soluble lithium polysulfides lead to an outstanding long‐term cycling performance and an ultralow decay of 0.016% per cycle over 600 cycles at 2C.

Boolean Biomaterials: Logic‐Based Delivery of Site‐Specifically Modified Proteins from Environmentally Responsive Hydrogel Biomaterials (Adv. Mater. 33/2019)

By Prathamesh Milind Gawade, Jared A. Shadish, Barry A. Badeau, Cole A. DeForest from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

In article number 1902462, Cole DeForest and co‐workers introduce a modular semisynthetic scheme to govern the release of site‐specifically modified proteins from hydrogel biomaterials following Boolean YES/OR/AND logic. This strategy permits independent and sequential release of multiple species from a homogeneous material in response to user‐specified combinations of environmental inputs.

Advances in Biomaterials and Technologies for Vascular Embolization

By Jingjie Hu, Hassan Albadawi, Brian W. Chong, Amy R. Deipolyi, Rahul A. Sheth, Ali Khademhosseini, Rahmi Oklu from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

Advances in biotechnology and material science have facilitated the development of embolic agents for vascular embolization. Both clinical and preclinical embolic agents, including mechanical occlusion devices, particulates, and liquids, are reviewed. The challenges and future insights in this field are also highlighted. An integrated and multidisciplinary approach may offer opportunities to revolutionize the next generation of embolic agents. Abstract Minimally invasive transcatheter embolization is a common nonsurgical procedure in interventional radiology used for the deliberate occlusion of blood vessels for the treatment of diseased or injured vasculature. A wide variety of embolic agents including metallic coils, calibrated microspheres, and liquids are available for clinical practice. Additionally, advances in biomaterials, such as shape‐memory foams, biodegradable polymers, and in situ gelling solutions have led to the development of novel preclinical embolic agents. The aim here is to provide a comprehensive overview of current and emerging technologies in endovascular embolization with respect to devices, materials, mechanisms, and design guidelines. Limitations and challenges in embolic materials are also discussed to promote advancement in the field.

In Situ Transmission Electron Microscopy for Energy Materials and Devices

By Zheng Fan, Liqiang Zhang, Daniel Baumann, Lin Mei, Yuxing Yao, Xidong Duan, Yumeng Shi, Jianyu Huang, Yu Huang, Xiangfeng Duan from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

The most recent developments in in situ transmission electron microscopy for studying green‐energy materials and devices such as rechargeable ion batteries, chemical fuel cells, and perovskite solar cells are reviewed. A critical view on the application of this technology on the long road toward a green‐energy future is provided. Abstract Energy devices such as rechargeable batteries, fuel cells, and solar cells are central to powering a renewable, mobile, and electrified future. To advance these devices requires a fundamental understanding of the complex chemical reactions, material transformations, and charge flow that are associated with energy conversion processes. Analytical in situ transmission electron microscopy (TEM) offers a powerful tool for directly visualizing these complex processes at the atomic scale in real time and in operando. Recent advancements in energy materials and devices that have been enabled by in situ TEM are reviewed. First, the evolutionary development of TEM nanocells from the open‐cell configuration to the closed‐cell, and finally the full‐cell, is reviewed. Next, in situ TEM studies of rechargeable ion batteries in a practical operation environment are explored, followed by applications of in situ TEM for direct observation of electrocatalyst formation, evolution, and degradation in proton‐exchange membrane fuel cells, and fundamental investigations of new energy materials such as perovskites for solar cells. Finally, recent advances in the use of environmental TEM and cryogenic electron microscopy in probing clean‐energy materials are presented and emerging opportunities and challenges in in situ TEM research of energy materials and devices are discussed.

Nanotransducers for Near‐Infrared Photoregulation in Biomedicine

By Jingchao Li, Hongwei Duan, Kanyi Pu from Wiley: Advanced Materials: Table of Contents. Published on Aug 13, 2019.

Near‐infrared (NIR) photoregulation provides a promising approach for remote control of biological events and innovation of new therapeutic modalities. The recent development of optical nanotransducers for NIR photoregulation applications, including photoregulation of neural activity, gene expression, and visual systems, as well as photochemical tissue bonding, are summarized. Abstract Photoregulation, which utilizes light to remotely control biological events, provides a precise way to decipher biology and innovate in medicine; however, its potential is limited by the shallow tissue penetration and/or phototoxicity of ultraviolet (UV)/visible light that are required to match the optical responses of endogenous photosensitive substances. Thereby, biologically friendly near‐infrared (NIR) light with improved tissue penetration is desired for photoregulation. Since there are a few endogenous biomolecules absorbing or emitting light in the NIR region, the development of molecular transducers is essential to convert NIR light into the cues for regulation of biological events. In this regard, optical nanomaterials able to convert NIR light into UV/visible light, heat, or free radicals are suitable for this task. Here, the recent developments of optical nanotransducers for NIR‐light‐mediated photoregulation in medicine are summarized. The emerging applications, including photoregulation of neural activity, gene expression, and visual systems, as well as photochemical tissue bonding, are highlighted, along with the design principles of nanotransducers. Moreover, the current challenges and perspectives in this field are discussed.

Squaramate‐Modified Nucleotides and DNA for Specific Cross‐Linking with Lysine‐Containing Peptides and Proteins

By Ivana Ivancová, Radek Pohl, Martin Hubálek, Michal Hocek from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 13, 2019.

A squaramate–dNTP building block was prepared and used for the enzymatic synthesis of reactive DNA for cross‐linking with amines, peptides, and proteins, without the need for an external reagent. This could be used to label DNA and to identify and study DNA‐binding proteins. Abstract Squaramate‐linked 2′‐deoxycytidine 5′‐O‐triphosphate was synthesized and found to be good substrate for KOD XL DNA polymerase in primer extension or PCR synthesis of modified DNA. The resulting squaramate‐linked DNA reacts with primary amines to form a stable diamide linkage. This reaction was used for bioconjugations of DNA with Cy5 and Lys‐containing peptides. Squaramate‐linked DNA formed covalent cross‐links with histone proteins. This reactive nucleotide has potential for other bioconjugations of nucleic acids with amines, peptides or proteins without need of any external reagent.

Synthesis of Polyethylene with In‐Chain α,β‐Unsaturated Ketone and Isolated Ketone Units: Pd‐Catalyzed Ring‐Opening Copolymerization of Cyclopropenone with Ethylene

By Xiaoming Wang, Falk William Seidel, Kyoko Nozaki from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 13, 2019.

Daisy chain: A C3 polar monomer unit was successfully incorporated into a polyethylene chain for the first time by the Pd‐catalyzed copolymerization of cyclopropenones with ethylene. A polyethylene‐containing α,β‐unsaturated ketone unit in the chain was obtained, possibly by coordination‐insertion of the carbonyl group and ring opening of the strained three‐membered cyclopropenone ring. Under different reaction conditions an isolated ketone structure was afforded as the major carbonyl unit, and was generated by the copolymerization of ethylene with CO formed in situ from cyclopropenone. Abstract Although various functionalized units can be incorporated into polyolefins by transition metal catalyzed coordination copolymerizations of nonfunctionalized olefins with polar functional monomers, the incorporated functional units are largely limited to a C1 unit from either CO or C2 units from vinyl monomers. Reported here is the Pd‐catalyzed copolymerization of ethylene with cyclopropenone, leading to incorporation of C3 units with functional groups, α,β‐unsaturated ketones, in the chain. Coordination‐insertion of the carbonyl group and ring opening of the strained three‐membered ring are proposed as the key steps in the mechanism. Under different reaction conditions an isolated ketone structure was afforded as the major carbonyl unit, and could be generated by the copolymerization of ethylene with CO formed in situ from cyclopropenone.

Fulminating Gold and Silver

By Curt Wentrup from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 13, 2019.

The painting Explosion in the alchemist's laboratory by Justus van Bentum (1670–1727) might depict a detonation of fulminating gold, giving off ruby‐red fumes. The Essay describes the history of preparation and uses of fulminating gold and silver from the late 1500s onward. Abstract This Essay deals with the fascinating and highly explosive compounds fulminating gold and fulminating silver, which are easily made by treatment of gold dissolved in aqua regia with ammonia, and by reaction of silver oxide or silver salts with ammonia, respectively. Fulminating gold in particular captivated the alchemists in the 16th to 18th centuries. Numerous preparations were described, as well as numerous attempts to make volatile, sublimable or distillable gold, and to use the products so obtained (which were most likely gold chlorides) to make the sought‐after tincture, which would “heal” the “impure” metals and transform them into gold, and equally be a panacea to cure all human illnesses.

Dirac Nodal Arc Semimetal PtSn4: An Ideal Platform for Understanding Surface Properties and Catalysis for Hydrogen Evolution

By Guowei Li, Chenguang Fu, Wujun Shi, Lin Jiao, Jiquan Wu, Qun Yang, Rana Saha, Machteld E. Kamminga, Abhay K. Srivastava, Enke Liu, Aliza N. Yazdani, Nitesh Kumar, Jian Zhang, Graeme R. Blake, Xianjie Liu, Mats Fahlman, Steffen Wirth, Gudrun Auffermann, Johannes Gooth, Stuart Parkin, Vidya Madhavan, Xinliang Feng, Yan Sun, Claudia Felser from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 13, 2019.

Putting the tin into plaTINum: The Dirac semimetal PtSn4 has a two‐dimensional layered structure. Intrinsic and stable surface states are found in the Pt layer of the PtSn4 single crystal. The p orbitals of Pt atoms of these robust surface states can deliver electrons efficiently for hydrogen reduction. PtSn4 thus acts as a benchmark electrocatalyst for hydrogen evolution. Abstract Conductivity, carrier mobility, and a suitable Gibbs free energy are important criteria that determine the performance of catalysts for a hydrogen evolution reaction (HER). However, it is a challenge to combine these factors into a single compound. Herein, we discover a superior electrocatalyst for a HER in the recently identified Dirac nodal arc semimetal PtSn4. The determined turnover frequency (TOF) for each active site of PtSn4 is 1.54 H2 s−1 at 100 mV. This sets a benchmark for HER catalysis on Pt‐based noble metals and earth‐abundant metal catalysts. We make use of the robust surface states of PtSn4 as their electrons can be transferred to the adsorbed hydrogen atoms in the catalytic process more efficiently. In addition, PtSn4 displays excellent chemical and electrochemical stabilities after long‐term exposure in air and long‐time HER stability tests.

O−O Bond Formation and Liberation of Dioxygen Mediated by N5‐Coordinate Non‐Heme Iron(IV) Complexes

By Nicole Kroll, Ina Speckmann, Marc Schoknecht, Jana Gülzow, Marek Diekmann, Johannes Pfrommer, Anika Stritt, Maria Schlangen, Andreas Grohmann, Gerald Hörner from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 13, 2019.

The O−O bond is efficiently formed and dioxygen stoichiometrically released in the reaction of non‐heme oxoiron(IV) complexes with meta‐chloroperbenzoic acid. High‐valent iron(IV) is identified as a resting state. It is suggested to be activated towards O–O coupling through concerted inner‐sphere transfer of an electron and a hydroxyl anion. Abstract Formation of the O−O bond is considered the critical step in oxidative water cleavage to produce dioxygen. High‐valent metal complexes with terminal oxo (oxido) ligands are commonly regarded as instrumental for oxygen evolution, but direct experimental evidence is lacking. Herein, we describe the formation of the O−O bond in solution, from non‐heme, N5‐coordinate oxoiron(IV) species. Oxygen evolution from oxoiron(IV) is instantaneous once meta‐chloroperbenzoic acid is administered in excess. Oxygen‐isotope labeling reveals two sources of dioxygen, pointing to mechanistic branching between HAT (hydrogen atom transfer)‐initiated free‐radical pathways of the peroxides, which are typical of catalase‐like reactivity, and iron‐borne O−O coupling, which is unprecedented for non‐heme/peroxide systems. Interpretation in terms of [FeIV(O)] and [FeV(O)] being the resting and active principles of the O−O coupling, respectively, concurs with fundamental mechanistic ideas of (electro‐) chemical O−O coupling in water oxidation catalysis (WOC), indicating that central mechanistic motifs of WOC can be mimicked in a catalase/peroxidase setting.

Phenothiazine Scope: Steric Strain Induced Planarization and Excimer Formation

By Deng‐Gao Chen, Yi Chen, Cheng‐Ham Wu, Yi‐An Chen, Meng‐Chi Chen, Jia‐An Lin, Chun‐Ying Huang, Jianhua Su, He Tian, Pi‐Tai Chou from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 13, 2019.

In ′plane′ view: Phenothiazine derivatives were designed and synthesized. In solution, the more‐strained structure (see Scheme) possesses a bent structure and undergoes photoinduced structural planarization (PISP). In the crystal, despite the absence of PISP, it exhibits prominent excimer emission as well as emission mechanochromism. Abstract Phenothiazine derivatives based on the 10‐phenyl‐10H‐phenothiazine (NAS) chromophore, namely 7‐phenyl‐7H‐benzo[c]phenothiazine (NAS‐1) and 12‐phenyl‐12H‐benzo[a]phenothiazine (NAS‐2), were designed and synthesized. NAS‐1 and NAS‐2 are constitutional isomers with different steric strains imposed on the phenothiazine core moiety. In solution, the more‐strained NAS‐2 possesses a bent structure and undergoes photoinduced structural planarization (PISP). In the crystal, despite the absence of PISP, bent NAS‐2 exhibits prominent excimer emission as well as emission mechanochromism, which is not observed in the planar‐like NAS and NAS‐1. This unconventional observation results from the bent core structure facilitating π–π stacking of the peripheral naphthalene moieties. Two‐photon‐coupled depth‐dependent emission shows spectral differences between the surface and kernel of the NAS‐2 crystal, and is believed to be a general phenomenon, at least in part, for materials exhibiting emission mechanochromism.

Strigolactones: Plant Hormones with Promising Features

By Harro J. Bouwmeester, Raymonde Fonne‐Pfister, Claudio Screpanti, Alain De Mesmaeker from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 13, 2019.

A rich field: The recently discovered class of plant hormones, the strigolactones, display unprecedented biological activity. Their use however is not without challenges: the synthesis of strigolactones is complicated and designing the desired activity a difficult task. This Minireview describes the current state of knowledge about the strigolactones and how synthetic analogs can be developed that can potentially contribute to the development of a sustainable agriculture. Abstract Almost 80 years after the discovery of the first plant hormone, auxin, a few years ago a new class of plant hormones, the strigolactones, was discovered. These molecules have unprecedented biological activity in a number of highly important biological processes in plants but also outside the plant in the rhizosphere, the layer of soil surrounding the roots of plants and teeming with life. The exploitation of this amazing biological activity is not without challenges: the synthesis of strigolactones is complicated and designing the desired activity a difficult task. This minireview describes the current state of knowledge about the strigolactones and how synthetic analogs can be developed that can potentially contribute to the development of a sustainable agriculture.

Cysteine SH and Glutamate COOH Contributions to [NiFe] Hydrogenase Proton Transfer Revealed by Highly Sensitive FTIR Spectroscopy

By Hulin Tai, Koji Nishikawa, Yoshiki Higuchi, Zong‐wan Mao, Shun Hirota from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 13, 2019.

Catalytic contributions: Protonated Cys546‐SH, H‐bonded Glu34‐COOH, and ordered water frequencies were observed for the Ni‐C, Ni‐L, and Ni‐SIa states of [NiFe] hydrogenase, showing that the organized proton transfer pathway during the catalytic reaction is regulated by the H‐bond network of Cys546, Glu34, and an ordered water molecule. Abstract A [NiFe] hydrogenase (H2ase) is a proton‐coupled electron transfer enzyme that catalyses reversible H2 oxidation; however, its fundamental proton transfer pathway remains unknown. Herein, we observed the protonation of Cys546‐SH and Glu34‐COOH near the Ni–Fe site with high‐sensitivity infrared difference spectra by utilizing Ni‐C‐to‐Ni‐L and Ni‐C‐to‐Ni‐SIa photoconversions. Protonated Cys546‐SH in the Ni‐L state was verified by the observed SH stretching frequency (2505 cm−1), whereas Cys546 was deprotonated in the Ni‐C and Ni‐SIa states. Glu34‐COOH was double H‐bonded in the Ni‐L state, as determined by the COOH stretching frequency (1700 cm−1), and single H‐bonded in the Ni‐C and Ni‐SIa states. Additionally, a stretching mode of an ordered water molecule was observed in the Ni‐L and Ni‐C states. These results elucidate the organized proton transfer pathway during the catalytic reaction of a [NiFe] H2ase, which is regulated by the H‐bond network of Cys546, Glu34, and an ordered water molecule.

Rapid Identification of Halogen Bonds in Co‐Crystalline Powders via 127I Nuclear Quadrupole Resonance Spectroscopy

By Patrick M. J. Szell, Lorraine Grébert, David L. Bryce from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 13, 2019.

127I can show you the bond: 127I NQR spectroscopy is established as a rapid probe of iodine–nitrogen halogen‐bond formation in a series of 1,4‐diiodobenzene co‐crystalline powders. The method is cross‐validated through testing on two previously unknown co‐crystals, demonstrating its predictive power. DFT computations reveal the origins of the observed spectral shifts. Abstract 127I nuclear quadrupole resonance (NQR) spectroscopy is established as a rapid and robust method to indicate the formation of iodine–nitrogen halogen bonds in co‐crystalline powders. Once the relevant spectral frequency range has been established, diagnostic 127I NQR spectra can be acquired in seconds. The method is demonstrated for a series of co‐crystals of 1,4‐diiodobenzene. Changes in the 127I quadrupolar coupling constant (CQ) by up to 74.4 MHz correlate with the length of the C−I donor covalent bond and inversely with the I⋅⋅⋅N halogen‐bond length. The predictive power of this technique is validated on two previously unknown co‐crystalline powders prepared mechanochemically. Single‐crystal growth via co‐sublimation and structure determination by single‐crystal X‐ray diffraction cross‐validates the findings. Natural localized molecular‐orbital analyses provide insight into the origins of the quadrupolar coupling constants.

[ASAP] Contact Engineering High-Performance n-Type MoTe2 Transistors

By Michal J. Mleczko†#, Andrew C. Yu†?, Christopher M. Smyth‡, Victoria Chen†, Yong Cheol Shin†, Sukti Chatterjee§, Yi-Chia Tsai†??, Yoshio Nishi†, Robert M. Wallace‡, and Eric Pop*†? from Nano Letters: Latest Articles (ACS Publications). Published on Aug 13, 2019.

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Nano Letters
DOI: 10.1021/acs.nanolett.9b02497

[ASAP] Force-Dependent Regulation of Talin–KANK1 Complex at Focal Adhesions

By Miao Yu†#, Shimin Le‡#, York-Christoph Ammon§#, Benjamin T. Goult?, Anna Akhmanova*§, and Jie Yan*†‡? from Nano Letters: Latest Articles (ACS Publications). Published on Aug 13, 2019.

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Nano Letters
DOI: 10.1021/acs.nanolett.9b01732

[ASAP] Two-Dimensional Quadrupole Topological Insulator in ?-Graphyne

By Bing Liu†§, Gan Zhao†§, Zhao Liu†, and Z. F. Wang*†‡ from Nano Letters: Latest Articles (ACS Publications). Published on Aug 13, 2019.

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Nano Letters
DOI: 10.1021/acs.nanolett.9b02719

[ASAP] High Yield Controlled Synthesis of Nano-Graphene Oxide by Water Electrolytic Oxidation of Glassy Carbon for Metal-Free Catalysis

By Qinwei Wei†‡?, Songfeng Pei†?, Guodong Wen†, Kun Huang†, Zhaohong Wu†‡, Zhibo Liu†, Wei Ma†‡, Hui-Ming Cheng†‡§, and Wencai Ren*†‡ from ACS Nano: Latest Articles (ACS Publications). Published on Aug 13, 2019.

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ACS Nano
DOI: 10.1021/acsnano.9b04447

[ASAP] Exciton Polarization and Renormalization Effect for Optical Modulation in Monolayer Semiconductors

By Jiang Pu*†, Keichiro Matsuki‡, Leiqiang Chu§?, Yu Kobayashi?, Shogo Sasaki?, Yasumitsu Miyata?, Goki Eda§?#, and Taishi Takenobu*†‡ from ACS Nano: Latest Articles (ACS Publications). Published on Aug 13, 2019.

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ACS Nano
DOI: 10.1021/acsnano.9b03563

[ASAP] Facile Tailoring of Multidimensional Nanostructured Sb for Sodium Storage Applications

By Haomiao Li†‡, Kangli Wang*†, Min Zhou†, Wei Li†‡, Hongwei Tao†, Ruxing Wang†, Shijie Cheng†, and Kai Jiang*† from ACS Nano: Latest Articles (ACS Publications). Published on Aug 13, 2019.

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ACS Nano
DOI: 10.1021/acsnano.9b04520

[ASAP] P(V) Reagents for the Scalable Synthesis of Natural and Modified Nucleoside Triphosphates

By Jen-Yu Liao†, Saikat Bala†, Arlene K. Ngor, Eric J. Yik, and John C. Chaput* from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 13, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b04728

[ASAP] Proton-Coupled Electron Transfer Drives Long-Range Proton Translocation in Bioinspired Systems

By Emmanuel Odella§‡, Brian L. Wadsworth§‡, S. Jimena Mora§‡, Joshua J. Goings†‡, Mioy T. Huynh†, Devens Gust§, Thomas A. Moore§, Gary F. Moore*§, Sharon Hammes-Schiffer*†, and Ana L. Moore*§ from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 13, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b06978

[ASAP] Designing Open Metal Sites in Metal–Organic Frameworks for Paraffin/Olefin Separations

By Mona H. Mohamed†‡, Yahui Yang§, Lin Li§, Sen Zhang§, Jonathan P. Ruffley§, Austin Gamble Jarvi†, Sunil Saxena†, Go¨tz Veser*§, J. Karl Johnson*§, and Nathaniel L. Rosi*†§ from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 13, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b06582

[ASAP] Nanoscale Mapping of Nonuniform Heterogeneous Nucleation Kinetics Mediated by Surface Chemistry

By Mei Wang†, Thilini U. Dissanayake†, Chiwoo Park‡, Karen Gaskell§, and Taylor J. Woehl*† from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 13, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b05225

[ASAP] Nitric Oxide-Activated “Dual-Key–One-Lock” Nanoprobe for in Vivo Molecular Imaging and High-Specificity Cancer Therapy

By Lili Teng‡, Guosheng Song‡, Yongchao Liu, Xiaoyu Han, Zhe Li, Youjuan Wang, Shuangyan Huan, Xiao-Bing Zhang*, and Weihong Tan from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 13, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b05901

[ASAP] Correction to ‘‘Molecular Design Strategy to Construct the Near-Infrared Fluorescent Probe for Selectively Sensing Human Cytochrome P450 2J2’’

By Jing Ning, Tao Liu, Peipei Dong, Wei Wang, Guangbo Ge, Bo Wang, Zhenlong Yu, Lei Shi, Xiangge Tian, Xiaokui Huo, Lei Feng*, Chao Wang, Chengpeng Sun, Jingnan Cui, Tony D. James, and Xiaochi Ma* from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 13, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b07996

[ASAP] Spotlights on Recent JACS Publications

By ACS Contributing Correspondents from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 13, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b08727

[ASAP] Total Synthesis and Structure Revision of (-)-Illisimonin A, a Neuroprotective Sesquiterpenoid from the Fruits of Illicium simonsii

By Alexander S. Burns and Scott D. Rychnovsky* from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 13, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b05065

[ASAP] Aryl–Fluoride Bond-Forming Reductive Elimination from Nickel(IV) Centers

By Elizabeth A. Meucci†, Alireza Ariafard‡, Allan J. Canty‡, Jeff W. Kampf†, and Melanie S. Sanford*† from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 13, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b06896

[ASAP] Direction of Chain Growth and Substrate Preferences of Shape, Elongation, Division, and Sporulation-Family Peptidoglycan Glycosyltransferases

By Michael A. Welsh§‡†, Kaitlin Schaefer§¶‡, Atsushi Taguchi§, Daniel Kahne¶, and Suzanne Walker*§ from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 13, 2019.

TOC Graphic

Journal of the American Chemical Society
DOI: 10.1021/jacs.9b06358

High-quality graphene transfer via directional etching of metal substrates

By Hongtao Wang from RSC - Nanoscale latest articles. Published on Aug 13, 2019.

Nanoscale, 2019, Advance Article
DOI: 10.1039/C9NR05315H, Paper
Xuewei Zhang, Zehao Wu, Haoran Zheng, Qiancheng Ren, Zhenxing Zou, Le Mei, Zilong Zhang, Yang Xia, Cheng-Te Lin, Pei Zhao, Hongtao Wang
The quality of chemical-vapor-deposited graphene can be significantly improved by directional removal of the underlying Cu substrate.
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Integrating Flexible Electrochemical Sensor into Microfluidic Chip for Simulating and Monitoring Vascular Mechanotransduction

By Zi‐He Jin, Yan‐Ling Liu, Wen‐Ting Fan, Wei‐Hua Huang from Wiley: Small: Table of Contents. Published on Aug 12, 2019.

The first integration of a flexible electrochemical sensor into a microfluidic vascular chip is reported. This allows simulating of in vivo physiological and biomechanical parameters of blood vessels, and simultaneously monitoring the mechanically‐induced biochemical signals in real time. Abstract As an interface between the blood flow and vessel wall, endothelial cells (ECs) are exposed to hemodynamic forces, and the biochemical molecules released from ECs–blood flow interaction are important determinants of vascular homeostasis. Versatile microfluidic chips have been designed to simulate the biological and physiological parameters of the human vascular system, but in situ and real‐time monitoring of the mechanical force–triggered signals during vascular mechanotransduction still remains a significant challenge. Here, such challenge is fulfilled for the first time, by preparation of a flexible and stretchable electrochemical sensor and its incorporation into a microfluidic vascular chip. This allows simulating of in vivo physiological and biomechanical parameters of blood vessels, and simultaneously monitoring the mechanically induced biochemical signals in real time. Specifically, the cyclic circumferential stretch that is actually exerted on endothelium but is hard to reproduce in vitro is successfully recapitulated, and nitric oxide signals under normal blood pressure, as well as reactive oxygen species signals under hypertensive states, are well documented. Here, the first integration of a flexible electrochemical sensor into a microfluidic chip is reported, therefore paving a way to evaluate in vitro organs by built‐in flexible sensors.

A Review on Graphene Fibers: Expectations, Advances, and Prospects

By Bo Fang, Dan Chang, Zhen Xu, Chao Gao from Wiley: Advanced Materials: Table of Contents. Published on Aug 12, 2019.

The features of graphene fibers are presented along four lines: preparation, morphology, structure–performance correlations, and state‐of‐the‐art applications. Starting from the principles, experiments, and keys to fabricate graphene fibers, the fundamental relationship between properties and structures, including both highly condensed structures for high performance and hierarchical structures for multiple functions, is presented, and their structural–functional integrated uses are explored. Abstract Graphene fiber (GF) is a macroscopically assembled fibrous material made of individual units of graphene and its derivatives. Beyond traditional carbon fibers, graphene building blocks consisting of regulable sizes and regular orientations of GF are expected to generate extreme mechanical and transport properties, as well as multiple functions in smart electronic fibrous devices and textiles. Here, the features of GF are presented along four lines: preparation, morphology, structure–performance correlations, and state‐of‐the‐art applications as flexible and wearable electronics. The principles, experiments, and keys of fabricating GF from graphite with different methods, focusing on the industrially viable mainstream strategy, wet spinning, are introduced. Then, the fundamental relationship between the mechanical and transport properties and the structure, including both highly condensed structures for high‐performance and hierarchical structures for multiple functions, is presented. The advances of GF based on structure–performance formulas boost its functional applications, especially in electronic devices. Finally, the possible promotion methods and structural–functional integrated applications of GF are discussed.

Recent Progress in CVD Growth of 2D Transition Metal Dichalcogenides and Related Heterostructures

By Yu Zhang, Yuyu Yao, Marshet Getaye Sendeku, Lei Yin, Xueying Zhan, Feng Wang, Zhenxing Wang, Jun He from Wiley: Advanced Materials: Table of Contents. Published on Aug 12, 2019.

The latest research advances in the chemical vapor deposition (CVD) synthesis of 2D transition metal dichalcogenides and related heterostructures/superlattices are comprehensively summarized. The controlled growth behavior, preparation strategies, and breakthroughs regarding the synthesis are also discussed. Finally, recent progress on the application of CVD‐grown 2D materials is presented with emphasis on the future prospects of these materials. Abstract In recent years, 2D layered materials have received considerable research interest on account of their substantial material systems and unique physicochemical properties. Among them, 2D layered transition metal dichalcogenides (TMDs), a star family member, have already been explored over the last few years and have exhibited excellent performance in electronics, catalysis, and other related fields. However, to fulfill the requirement for practical application, the batch production of 2D TMDs is essential. Recently, the chemical vapor deposition (CVD) technique was considered as an elegant alternative for successfully growing 2D TMDs and their heterostructures. The latest research advances in the controllable synthesis of 2D TMDs and related heterostructures/superlattices via the CVD approach are illustrated here. The controlled growth behavior, preparation strategies, and breakthroughs on the synthesis of new 2D TMDs and their heterostructures, as well as their unique physical phenomena, are also discussed. Recent progress on the application of CVD‐grown 2D materials is revealed with particular attention to electronics/optoelectronic devices and catalysts. Finally, the challenges and future prospects are considered regarding the current development of 2D TMDs and related heterostructures.

Genetic Logic Gates Enable Patterning of Amyloid Nanofibers

By Ebuzer Kalyoncu, Recep Erdem Ahan, Cemile Elif Ozcelik, Urartu Ozgur Safak Seker from Wiley: Advanced Materials: Table of Contents. Published on Aug 12, 2019.

Synthetic‐biology‐enabled devices can be used for biomaterial assembly and patterning. Biological polymers including biofilm fibers and spider silk are formed by specific proteins that are synthetized in monomeric form and assembled into higher ordered structures. Recombinase‐integrated genetic logic gates are employed to control patterning of bacterial biofilm nanofibers for the assembly of gold nanoparticles. Abstract Distinct spatial patterning of naturally produced materials is observed in many cellular structures and even among communities of microorganisms. Reoccurrence of spatially organized materials in all branches of life is clear proof that organization is beneficial for survival. Indeed, organisms can trick the evolutionary process by using organized materials in ways can help the organism to avoid unexpected conditions. To expand the toolbox for synthesizing patterned living materials, Boolean type “AND” and “OR” control of curli fibers expression is demonstrated using recombinases. Logic gates are designed to activate the production of curli fibers. The gates can be used to record the presence of input molecules and give output as CsgA expression. Two different curli fibers (CsgA and CsgA‐His‐tag) production are then selectively activated to explore distribution of monomers upon coexpression. To keep track of the composition of fibers, CsgA‐His‐tag proteins are labeled with nickel–nitrilotriacetic acid (Ni–NTA‐) conjugated gold nanoparticles. It is observed that an organized living material can be obtained upon inducing the coexpression of different CsgA fibers. It is foreseen that living materials with user‐defined curli composition hold great potential for the development of living materials for many biomedical applications.

Multifunctional Chemical Linker Imidazoleacetic Acid Hydrochloride for 21% Efficient and Stable Planar Perovskite Solar Cells

By Jiangzhao Chen, Xing Zhao, Seul‐Gi Kim, Nam‐Gyu Park from Wiley: Advanced Materials: Table of Contents. Published on Aug 12, 2019.

A multifunctional chemical linker of 4‐imidazoleacetic acid hydrochloride (ImAcHCl) between SnO2 and a perovskite layer improves the average power conversion efficiency from 18.60% to 20.22% due to the upward shift of band position, reduced nonradiative recombination, and improved carrier lifetime. In addition, interfacial engineering improves thermal and moisture stability. Abstract Chemical interaction at a heterojunction interface induced by an appropriate chemical linker is of crucial importance for high efficiency, hysteresis‐less, and stable perovskite solar cells (PSCs). Effective interface engineering in PSCs is reported via a multifunctional chemical linker of 4‐imidazoleacetic acid hydrochloride (ImAcHCl) that can provide a chemical bridge between SnO2 and perovskite through an ester bond with SnO2 via esterification reaction and an electrostatic interaction with perovskite via imidazolium cation in ImAcHCl and iodide anion in perovskite. In addition, the chloride anion in ImAcHCl plays a role in the improvement of crystallinity of perovskite film crystallinity. The introduction of ImAcHCl onto SnO2 realigns the positions of the conduction and valence bands upwards, reduces nonradiative recombination, and improves carrier life time. As a consequence, average power conversion efficiency (PCE) is increased from 18.60% ± 0.50% to 20.22% ± 0.34% before and after surface modification, respectively, which mainly results from an enhanced voltage from 1.084 ± 0.012 V to 1.143 ± 0.009 V. The best PCE of 21% is achieved by 0.1 mg mL−1 ImAcHCl treatment, along with negligible hysteresis. Moreover, an unencapsulated device with ImAcHCl‐modified SnO2 shows much better thermal and moisture stability than unmodified SnO2.

Room‐Temperature Stimulated Emission and Lasing in Recrystallized Cesium Lead Bromide Perovskite Thin Films

By Neda Pourdavoud, Tobias Haeger, Andre Mayer, Piotr Jacek Cegielski, Anna Lena Giesecke, Ralf Heiderhoff, Selina Olthof, Stefan Zaefferer, Ivan Shutsko, Andreas Henkel, David Becker‐Koch, Markus Stein, Marko Cehovski, Ouacef Charfi, Hans‐Hermann Johannes, Detlef Rogalla, Max Christian Lemme, Martin Koch, Yana Vaynzof, Klaus Meerholz, Wolfgang Kowalsky, Hella‐Christin Scheer, Patrick Görrn, Thomas Riedl from Wiley: Advanced Materials: Table of Contents. Published on Aug 12, 2019.

Highly efficient photoluminescence (PL‐QY = 68%), amplified spontaneous emission, and low‐threshold lasing in thin films of cesium lead bromide at room temperature are shown. Importantly, the films are not based on nanocrystals or quantum dots but consist of extended continuous layers, that are formed upon recrystallization of as‐deposited layers by thermal imprint. Abstract Cesium lead halide perovskites are of interest for light‐emitting diodes and lasers. So far, thin‐films of CsPbX3 have typically afforded very low photoluminescence quantum yields (PL‐QY

Modulating the Charge Transport in 2D Semiconductors via Energy‐Level Phototuning

By Haixin Qiu, Yuda Zhao, Zhaoyang Liu, Martin Herder, Stefan Hecht, Paolo Samorì from Wiley: Advanced Materials: Table of Contents. Published on Aug 12, 2019.

Optically switchable field‐effect transistors (FETs) are realized by decorating the surface of 2D WSe2 and black phosphorene with photochromic diarylethenes. Both electron and hole transport can be efficiently and reversibly modulated as a result of light irradiation at different wavelengths. These FETs also show five distinguishable output current levels with high‐accuracy readout, demonstrating their huge potential for multilevel memories. Abstract The controlled functionalization of semiconducting 2D materials (2DMs) with photoresponsive molecules enables the generation of novel hybrid structures as active components for the fabrication of high‐performance multifunctional field‐effect transistors (FETs) and memories. This study reports the realization of optically switchable FETs by decorating the surface of the semiconducting 2DMs such as WSe2 and black phosphorus with suitably designed diarylethene (DAE) molecules to modulate their electron and hole transport, respectively, without sacrificing their pristine electrical performance. The efficient and reversible photochemical isomerization of the DAEs between the open and the closed isomer, featuring different energy levels, makes it possible to generate photoswitchable charge trapping levels, resulting in the tuning of charge transport through the 2DMs by alternating illumination with UV and visible light. The device reveals excellent data‐retention capacity combined with multiple and well‐distinguished accessible current levels, paving the way for its use as an active element in multilevel memories.

Visible‐Light‐Induced Self‐Organized Helical Superstructure in Orientationally Ordered Fluids

By Hao Wang, Hari Krishna Bisoyi, Michael E. McConney, Augustine M. Urbas, Timothy J. Bunning, Quan Li from Wiley: Advanced Materials: Table of Contents. Published on Aug 12, 2019.

Light‐induced phenomena abound in nature and have served as inspiration in the development of light‐driven materials for device applications. In this work, visible‐light‐induced formation of a helical superstructure is accomplished in orientationally ordered fluids, i.e., nematic liquid crystals, enabled by a visible‐light‐driven chiral molecular switch. Abstract Light‐induced phenomena occurring in nature and in synthetic materials are fascinating and have been exploited for technological applications. Here visible‐light‐induced formation of a helical superstructure is reported, i.e., a cholesteric liquid crystal phase, in orientationally ordered fluids, i.e., nematic liquid crystals, enabled by a visible‐light‐driven chiral molecular switch. The cyclic‐azobenzene‐based chiral molecular switch exhibits reversible photoisomerization in response to visible light of different wavelengths due to the band separation of n–π* transitions of its trans‐ and cis‐isomers. Green light (530 nm) drives the trans‐to‐cis photoisomerization whereas the cis‐to‐trans isomerization process of the chiral molecular switch can be caused by blue light (440 nm). It is observed that the helical twisting power of this chiral molecular switch increases upon irradiation with green light, which enables reversible induction of helical superstructure in nematic liquid crystals containing a very small quantity of the molecular switch. The occurrence of the light‐induced helical superstructure enables the formation of diffraction gratings in cholesteric films.

Genetically Programmable Self‐Regenerating Bacterial Hydrogels

By Anna M. Duraj‐Thatte, Noémie‐Manuelle Dorval Courchesne, Pichet Praveschotinunt, Jarod Rutledge, Yuhan Lee, Jeffrey M. Karp, Neel S. Joshi from Wiley: Advanced Materials: Table of Contents. Published on Aug 12, 2019.

Biofabricated hydrogels have the ability to grow and self‐regenerate in the gastrointestinal tract. Genetic programming enables customization to interact with different tissues of the gastrointestinal tract selectively and to fabricate living hydrogel materials. This novel engineered living material lays a foundation for therapeutic applications in the gut, especially those that may benefit from a cohesive material with extended residence times. Abstract A notable challenge for the design of engineered living materials (ELMs) is programming a cellular system to assimilate resources from its surroundings and convert them into macroscopic materials with specific functions. Here, an ELM that uses Escherichia coli as its cellular chassis and engineered curli nanofibers as its extracellular matrix component is demonstrated. Cell‐laden hydrogels are created by concentrating curli‐producing cultures. The rheological properties of the living hydrogels are modulated by genetically encoded factors and processing steps. The hydrogels have the ability to grow and self‐renew when placed under conditions that facilitate cell growth. Genetic programming enables the gels to be customized to interact with different tissues of the gastrointestinal tract selectively. This work lays a foundation for the application of ELMs with therapeutic functions and extended residence times in the gut.

Enabling Robust Self‐Folding Origami by Pre‐Biasing Vertex Buckling Direction

By Ji‐Hwan Kang, Hyunki Kim, Christian D. Santangelo, Ryan C. Hayward from Wiley: Advanced Materials: Table of Contents. Published on Aug 12, 2019.

Robust self‐folding of microscale hydrogel origami is demonstrated by prescribing the buckling direction of vertices to avoid misfolding along distractor branches that bifurcate from the flat state. Followed by thermally responsive activation of hinges to their programmed angles, this allows for robust self‐folding even for multi‐vertex origami designs that frequently fail to fold properly in the absence of vertex biasing. Abstract Self‐folding is a powerful approach to fabricate materials with complex 3D forms and advanced properties using planar patterning steps, but suffers from intrinsic limitations in robustness due to the highly bifurcated nature of configuration space around the flat state. Here, a simple mechanism is introduced to achieve robust self‐folding of microscale origami by separating actuation into two discrete steps using different thermally responsive hydrogels. First, the vertices are pre‐biased to move in the desired direction from the flat state by selectively swelling one of the two hydrogels at high temperature. Subsequently, the creases are folded toward their target angles by activating swelling of the second hydrogel upon cooling to room temperature. Since each vertex can be individually programmed to move upward or downward, it is possible to robustly select the desired branch even in multi‐vertex structures with reasonably high complexity. This strategy provides key new principles for designing shaping‐morphing materials that avoid undesired distractor states, expanding their potential applications in areas such as soft robotics, sensors, mechanical metamaterials, and deployable devices.

Simultaneous Bottom‐Up Interfacial and Bulk Defect Passivation in Highly Efficient Planar Perovskite Solar Cells using Nonconjugated Small‐Molecule Electrolytes

By Ding Zheng, Ruixiang Peng, Gang Wang, Jenna Leigh Logsdon, Binghao Wang, Xiaobing Hu, Yao Chen, Vinayak P. Dravid, Michael R. Wasielewski, Junsheng Yu, Wei Huang, Ziyi Ge, Tobin J. Marks, Antonio Facchetti from Wiley: Advanced Materials: Table of Contents. Published on Aug 12, 2019.

Nonconjugated multi‐zwitterionic small‐molecule electrolyte (NSE) molecules in perovskite solar cells (PSCs) act as both charge‐extracting layers for barrier‐free cathode charge collection but also as charged defect fillers in perovskite bulk and interfaces by spontaneous bottom‐up passivation. Thus, the NSE‐based PSCs deliver PCEs as high as 21.18% with an ultrahigh VOC of 1.19 V, suppressed hysteresis, and enhanced stability. Abstract Recent perovskite solar cell (PSC) advances have pursued strategies for reducing interfacial energetic mismatches to mitigate energy losses, as well as to minimize interfacial and bulk defects and ion vacancies to maximize charge transfer. Here nonconjugated multi‐zwitterionic small‐molecule electrolytes (NSEs) are introduced, which act not only as charge‐extracting layers for barrier‐free charge collection at planar triple cation PSC cathodes but also passivate charged defects at the perovskite bulk/interface via a spontaneous bottom‐up passivation effect. Implementing these synergistic properties affords NSE‐based planar PSCs that deliver a remarkable power conversion efficiency of 21.18% with a maximum VOC = 1.19 V, in combination with suppressed hysteresis and enhanced environmental, thermal, and light‐soaking stability. Thus, this work demonstrates that the bottom‐up, simultaneous interfacial and bulk trap passivation using NSE modifiers is a promising strategy to overcome outstanding issues impeding further PSC advances.

Mechanoresponsive Polymerized Liquid Metal Networks

By Carl Thrasher, Zachary Farrell, Nicholas Morris, Carson Willey, Christopher Tabor from Wiley: Advanced Materials: Table of Contents. Published on Aug 12, 2019.

Core–shell liquid metal particles functionalized with acrylate ligands are polymerized to create cross‐linked particle networks. When these polymerized liquid metal networks are stretched, their constituent particles rupture and the network transitions from insulating to conductive. These networks autonomously form hierarchical structures which help maintain stable electrical behavior under high strains and exhibit excellent performance as stretchable conductors and heaters. Abstract Room‐temperature liquid metals, such as nontoxic gallium alloys, show enormous promise to revolutionize stretchable electronics for next‐generation soft robotic, e‐skin, and wearable technologies. Core–shell particles of liquid metal with surface‐bound acrylate ligands are synthesized and polymerized together to create cross‐linked particle networks comprising >99.9% liquid metal by weight. When stretched, particles within these polymerized liquid metal networks (Poly‐LMNs) rupture and release their liquid metal payload, resulting in a rapid 108‐fold increase in the network's conductivity. These networks autonomously form hierarchical structures that mitigate the deleterious effects of strain on electronic performance and give rise to emergent properties. Notable characteristics include nearly constant resistances over large strains, electronic strain memory, and increasing volumetric conductivity with strain to over 20 000 S cm−1 at >700% elongation. Furthermore, these Poly‐LMNs exhibit exceptional performance as stretchable heaters, retaining 96% of their areal power across relevant physiological strains. Remarkable electromechanical properties, responsive behaviors, and facile processing make Poly‐LMNs ideal for stretchable power delivery, sensing, and circuitry.

Highly Ordered N‐Doped Carbon Dots Photosensitizer on Metal–Organic Framework‐Decorated ZnO Nanotubes for Improved Photoelectrochemical Water Splitting

By Hyungkyu Han, Frantisek Karlicky, Sudhagar Pitchaimuthu, Sun Hae Ra Shin, Aiping Chen from Wiley: Small: Table of Contents. Published on Aug 12, 2019.

A unique combination of metal–organic frameworks decorated on 1D zinc oxide (ZnO) nanotubes as host and nitrogen‐doped carbon dots (N‐CDs) as guest species is explored on account of its potential applications in photoelectrochemical water splitting performance. The experimental results corroborated with theoretical analysis to prove that 1D ZnO nanotubes with homogeneously anchored N‐CDs by a zeolitic imidazolate framework‐8 exhibit superior photocurrent density. Abstract In spite of having several advantages such as low cost, high chemical stability, and environmentally safe and benign synthetic as well as operational procedures, the full potential of carbon dots (CDs) is yet to be explored as photosensitizers due to the challenges associated with the fabrication of well‐arrayed CDs with many other photocatalytic heterostructures. In the present study, a unique combination of metal–organic framework (MOF)‐decorated zinc oxide (ZnO) 1D nanostructures as host and CDs as guest species are explored on account of their potential application in photoelectrochemical (PEC) water splitting performance. The synthetic strategy to incorporate well‐defined nitrogen‐doped carbon dots (N‐CDs) arrays onto a zeolitic imidazolate framework‐8 (ZIF‐8) anchored on ZnO 1D nanostructures allows a facile unification of different components which subsequently plays a decisive role in improving the material's PEC water splitting performance. Simple extension of such strategies is expected to offer significant advantages for the preparation of CD‐based heterostructures for photo(electro)catalytics and other related applications.

Facilitating Gold Redox Catalysis with Electrochemistry: An Efficient “Chemical‐Oxidant‐Free” Approach

By Xiaohan Ye, Pengyi Zhao, Shuyao Zhang, Yanbin Zhang, Qilin Wang, Chuan Shan, Lukasz Wojtas, Hao Guo, Hao Chen, Xiaodong Shi from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 12, 2019.

Due to the high oxidation potential between Au(I) and Au(III), gold redox catalysis requires at least stoichiometric amounts of a strong oxidant. We herein report the first example of an electrochemical approach in promoting gold‐catalyzed oxidative coupling of terminal alkynes. Oxidation of Au(I) to Au(III) was successfully achieved through anode oxidation, which enabled facile access to either symmetrical or unsymmetrical conjugated diynes via homo‐coupling or cross‐coupling. This report extends the reaction scope of this transformation to substrates that are not compatible with strong chemical oxidants and potentiates the versatility of gold redox chemistry through the utilization of electrochemical oxidative conditions.

Cooperative Self‐Assembly of Pyridine‐2,6‐Diimine‐Linked Macrocycles into Mechanically Robust Nanotubes

By Michael Strauss, Darya Asheghali, Austin Evans, Rebecca Li, Anton Chavez, Chao Sun, Matthew L. Becker, William R. Dichtel from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 12, 2019.

Nanotubes assembled from macrocyclic precursors offer a unique combination of low dimensionality, structural rigidity, and distinct interior and exterior microenvironments. Usually the weak stacking energies of macrocycles limit the length and mechanical strength of the resultant nanotubes. Imine‐linked macrocycles were recently found to assemble into high‐aspect ratio (>10^3), lyotropic nanotubes in the presence of excess acid. Yet these harsh conditions are incompatible with many functional groups and processing methods, and lower acid loadings instead catalyze macrocycle degradation. Here we report pyridine‐2,6‐diimine‐linked macrocycles that assemble into high‐aspect ratio nanotubes in the presence of less than 1 equiv of CF3CO2H per macrocycle. Analysis by gel permeation chromatography and fluorescence spectroscopy revealed a cooperative self‐assembly mechanism. The low acid concentrations needed to induce assembly enabled nanofibers to be obtained by touch‐spinning, which exhibit higher Young’s moduli (1.33 GPa) than many synthetic polymers and biological filaments. These findings represent a breakthrough in the design of inverse chromonic liquid crystals, as assembly under such mild conditions will enable the design of structurally diverse and mechanically robust nanotubes from synthetically accessible macrocycles.

Efficient Delivery of a Gene Editing Protein to Stem Cells via Peptide Brush Polymers

By Nathan C. Gianneschi, Angela Blum, David Nelles, Francisco Hidalgo, Mollie Touve, Deborah Sim, Assael A. Madrigal, Gene Yeo from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 12, 2019.

The scarcity of effective means to deliver functional proteins to living cells is a central problem in biotechnology and medicine. Stem cells present a particular opportunity to the field because of their technological and potential medical utility yet they are intransigent to most biomolecule transduction methods. Here we report the efficient delivery of an active DNA‐modifying enzyme to human stem cells via high‐density cell penetrating peptide brush polymers. Cre recombinase is mixed with a fluorophore‐tagged polymer carrier and then applied directly to induced pluripotent stem cells or HEK293 cells. This results in efficient delivery of Cre protein as measured by activation of a genomically‐integrated Cre‐mediated recombination reporter. We observed that brush polymer formulations utilizing cell penetrating peptides promoted Cre delivery but oligopeptides alone or oligopeptides displayed on nanoparticles did not. Overall, we report the efficient delivery of a genome‐modifying enzyme to stem cells that may be generalizable to other, difficult‐to‐transduce cell types.

Nano‐ferroelectric for high efficiency overall water splitting under ultrasonic vibration

By Ran Su, H. Alex Hsain, Ming Wu, Dawei Zhang, Xinghao Hu, Zhipeng Wang, Xiaojing Wang, Fa-tang Li, Xuemin Chen, Lina Zhu, Yong Yang, Yaodong Yang, Xiaojie Lou, Stephen J. Pennycook from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 12, 2019.

Piezocatalysis, converting mechanical vibration into chemical energy, has emerged as a promising candidate for water‐splitting technology. However, the efficiency of the hydrogen production is quite limited. We herein report well‐defined 10 nm BaTiO3 nanoparticles (NPs) characterized by a large electro‐mechanical coefficient which induces a high piezoelectric effect. Atomic‐resolution high angle annular dark field scanning transmission electron microscopy (HAADF‐STEM) and scanning probe microscopy (SPM) suggests that piezoelectric BaTiO3 NPs display a coexistence of multiple phases with low energy barriers and polarization anisotropy which results in a high electro‐mechanical coefficient. Landau free energy modeling also confirms that the greatly reduced polarization anisotropy facilitates polarization rotation. Employing the high piezoelectric properties of BaTiO3 NPs, we demonstrate an overall water‐splitting process with the highest hydrogen production efficiency hitherto reported, with a H2 production rate of 655 μmolg‐1h‐1, which could rival excellent photocatalysis system. This study highlights the potential of piezoelectric catalysis for overall water splitting.

Nitrogen‐Doped Hexapole [7]Helicene vs Its All‐Carbon Analogue

By Xiaoyu Guo, Ziyong Yuan, Yanpeng Zhu, Zhihao Li, Ruikang Huang, Zeming Xia, Weixiong Zhang, Yang Li, Jiaobing Wang from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 12, 2019.

Two synthetic nanographenes (NGs) were prepared. One is doped with nitrogen, N‐H7H; the other is its all‐carbon analogue, C‐H7H. Both are hexapole [7]helicenes (H7Hs), and their structures are identified by single crystal X‐ray diffraction. Sharp contrasts in absorption (absλmax, 683 vs 593 nm), emission (emλmax, 894 vs 777 nm), and electrochemical behaviour (oxE1, 0.28 vs 0.53 V) between N‐H7H and C‐H7H were observed, and the origin of these changes was rationalized by theoretical calculations. Studies on N‐H7H and C‐H7H set a clear example to elucidate the remarkable effects of N‐doping on NGs’ physical properties.

Gas‐Phase Dehydrogenation of Alkanes: C‐H Activation by a Graphene‐Supported Nickel Single‐Atom Catalyst Model

By Scott Gronert, Michael Borrome from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 12, 2019.

A gas‐phase anionic nickel(0) fluorenyl complex is shown to effect the dehydrogenation of linear, branched, and cyclic alkanes via C‐H activation. It performs dehydrogenations via a C‐H insertion followed by β‐hydride elimination. When given energy via collision‐induced dissociation, the system is capable of second and third dehydrogenations to form dienes and aromatics such as benzene. Kinetic isotope effects and DFT calculations completed at the M06/6‐311+G** level support the proposed mechanism. The metal complex can act as an experimental model for graphene‐supported nickel single‐atom catalysts and suggests that these catalysts are capable of alkane dehydrogenation via C‐H activation.

Wed 11 Sep 15:00: Achieving Redox Signalling specificity through Spatiotemporal and Chemical approaches

From All Talks (aka the CURE list). Published on Aug 12, 2019.

Achieving Redox Signalling specificity through Spatiotemporal and Chemical approaches

Redox signalling is a form of signal transduction that starts with the production of hydrogen peroxide and proceeds through the reversible oxidation of cysteine-thiol side-chains of proteins. It is clear that redox signalling leads only to oxidation of very specific proteins, but this is in apparent conflict with the chemical simplicity of H2O2 . Furthermore, most cysteines found to play a role in redox signalling have a relatively low reactivity to H2O2 compared to the catalytic cysteines in dedicated H2O2 scavenging enzymes. It is therefore not surprising that understanding how specificity and reactivity of Cysteine oxidation is being achieved in redox signalling is arguably the biggest question in the field. Recent studies have described cases in which Peroxiredoxins, dedicated H2O2 scavengers, after oxidation can partake in a redox relay reaction to oxidise cysteines in a client protein. We have undertaken extensive quantitative mass-spectrometry studies that suggest that 1) Peroxiredoxin mediated redox relay is a wide-spread phenomenon, 2) Each of the five human 2-Cys peroxiredoxins have a preferred set of targets for the redox relay reaction and 3) redox relay can take place by two distinct molecular mechanisms that could aid in the cellular response to different levels of H2O2 . Another layer of specificity in redox signalling that has been proposed is through spatiotemproral control of H2O2 production by for instance mitochondria, but good model systems to study this have been lacking. Cell polarization requires the dynamic regulation of signaling cascades in both time and space, making it an attractive model to study localized, subcellular (redox)signalling. We take advantage of this and use the C. elegans early embryo, one of the most-studied systems for cell polarization, to analyze the spatiotemporal regulation of redox signaling. We find that, coinciding with polarization, a subgroup of mitochondria relocates to the cell membrane at the site of symmetry breaking. After this, mitochondria become highly motile and localize closely to the posterior cortex of the embryo. An ultrasensitive H2O2 -specific sensor that we optimized for live imaging in C. elegans shows that mitochondrial relocation to the cell membrane is accompanied by a striking increase in cortical H2O2 –levels. Furthermore, mitochondrial H2O2 directly influences polarization, since compounds that alter mitochondrial H2O2 -production affect symmetry breaking and maximal polarization. Our observations show that redox signalling can indeed be initiated by the local production of H2O2 , and that cell polarization is regulated by redox signalling. Collectively these data suggest that redox signalling specificity can be regulated both by differences in the chemical properties of peroxiredoxin-mediated redox-relay targets and by spatiotemporal control of H2O2 production.

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Oxidation of Reduced Ceria by Incorporation of Hydrogen

By Hans-Joachim Freund, Zhaorui Li, Kristin Werner, Kun Qian, Rui You, Agata Płucienik, Aiping Jia, Lihui Wu, Liyuan Zhang, Haibin Pan, Helmut Kuhlenbeck, Shamil Shaikhutdinov, Weixin Huang from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 12, 2019.

The interaction of hydrogen with reduced ceria (CeO2‐x) powders and CeO2‐x(111) thin films was studied using several characterization techniques including TEM, XRD, LEED, XPS, RPES, EELS, ESR, and TDS. The results clearly indicate that both in reduced ceria powders as well as in reduced single crystal ceria films hydrogen may form hydroxyls at the surface and hydride species below the surface. The formation of hydrides is clearly linked to the presence of oxygen vacancies and is accompanied by the transfer of an electron from a Ce3+ species to hydrogen, which results in the formation of Ce4+, and thus in oxidation of ceria.

Carbon Nanotube Yarn for Fiber‐Shaped Electrical Sensors, Actuators, and Energy Storage for Smart Systems

By Yongwoo Jang, Sung Min Kim, Geoffrey M. Spinks, Seon Jeong Kim from Wiley: Advanced Materials: Table of Contents. Published on Aug 12, 2019.

Carbon nanotubes (CNTs) are currently the most promising material for fiber‐based smart systems. The high mechanical strength and electrical conductivity of CNT yarns have created initial interest in using these materials for smart electronic applications, leading to new types of sensors, actuators, and energy storage devices in integrated smart electronic systems. Abstract Smart systems are those that display autonomous or collaborative functionalities, and include the ability to sense multiple inputs, to respond with appropriate operations, and to control a given situation. In certain circumstances, it is also of great interest to retain flexible, stretchable, portable, wearable, and/or implantable attributes in smart electronic systems. Among the promising candidate smart materials, carbon nanotubes (CNTs) exhibit excellent electrical and mechanical properties, and structurally fabricated CNT‐based fibers and yarns with coil and twist further introduce flexible and stretchable properties. A number of notable studies have demonstrated various functions of CNT yarns, including sensors, actuators, and energy storage. In particular, CNT yarns can operate as flexible electronic sensors and electrodes to monitor strain, temperature, ionic concentration, and the concentration of target biomolecules. Moreover, a twisted CNT yarn enables strong torsional actuation, and coiled CNT yarns generate large tensile strokes as an artificial muscle. Furthermore, the reversible actuation of CNT yarns can be used as an energy harvester and, when combined with a CNT supercapacitor, has promoted the next‐generation of energy storage systems. Here, progressive advances of CNT yarns in electrical sensing, actuation, and energy storage are reported, and the future challenges in smart electronic systems considered.

Real‐Time Quantification of Cell Internalization Kinetics by Functionalized Bioluminescent Nanoprobes

By Di Wu, Yilong Yang, Pengcheng Xu, Duo Xu, Yang Liu, Roxanne Castillo, Ran Yan, Jie Ren, George Zhou, Chaoyong Liu, Meng Qin, Juanjuan Du, Lihua Hou, Irvin Chen, Chunsheng Kang, Lihua Jin, Jing Wen, Wei Chen, Yunfeng Lu from Wiley: Advanced Materials: Table of Contents. Published on Aug 12, 2019.

A real‐time method of quantifying cell internalization kinetics is developed using functionalized firefly‐luciferase nanocapsules as the probe, which is an effective tool for the study of cell internalization, drug development, and cancer therapy. Abstract Cells transport mass dynamically, crossing cell membranes to maintain metabolism and systemic homeostasis, through which biomolecules are also delivered to cells for gene editing, cell reprograming, therapy, and other purposes. Quantifying the translocation kinetics is fundamentally and clinically essential, but remains limited by fluorescence‐based technologies, which are semi‐quantitative and only provide kinetics information at cellular level or in discrete time. Herein, a real‐time method of quantifying cell internalization kinetics is reported using functionalized firefly‐luciferase nanocapsules as the probe. This quantitative assay will facilitate the rational design of delivery vectors and enable high‐throughput screening of peptides and other functional molecules, constituting an effective tool for broad applications, including drug development and cancer therapy.

Bioinspired Metamaterials: Multibands Electromagnetic Wave Adaptability and Hydrophobic Characteristics

By Lingxi Huang, Yuping Duan, Xuhao Dai, Yuansong Zeng, Guojia Ma, Yi Liu, Shaohua Gao, Weiping Zhang from Wiley: Small: Table of Contents. Published on Aug 12, 2019.

Inspired by the moth eye surface structure, state‐of‐the‐art hierarchical metamaterials with broadband absorption of microwaves are designed and prepared. The hierarchical metamaterials also demonstrate multibands adaptability. Microwave‐infrared compatible manipulation, anti‐reflection and color‐changing, ultraviolet shielding, and self‐cleaning are realized simultaneously, which have great potential application in the stealth and camouflage field. Abstract Although various photonic devices inspired by natural materials have been developed, there is no research focusing on multibands adaptability, which is not conducive to the advancement of materials science. Herein, inspired by the moth eye surface model, state‐of‐the‐art hierarchical metamaterials (MMs) used as tunable devices in multispectral electromagnetic‐waves (EMWs) frequency range, from microwave to ultraviolet (UV), are designed and prepared. Experimentally, the robust broad bandwidth of microwave absorption greater than 90% (reflection loss (RL)

Oxygen‐Tolerant Hydrogen Peroxide Reduction Catalysts for Reliable Noninvasive Bioassays

By Zhenyao Ding, Liping Chen, Dandan Wang, Hang Zhou, Lu Zhou, Xing Zhu, Lei Jiang, Xinjian Feng from Wiley: Small: Table of Contents. Published on Aug 12, 2019.

A series of O2‐tolerant H2O2 reduction catalysts are demonstrated, which enable the development of H2O2 cathodic reaction‐based noninvasive bioassays for selective detection of low concentration of analytes, including but not limited to glucose and lactate, while in the presence of a number of endogenous/exogenous interferents in biofluid. Abstract Noninvasive bioassays based on the principle of a hydrogen peroxide (H2O2) cathodic reaction are highly desirable for low concentration analyte detection within biofluids since the reaction is immune to interference from oxidizable species. However, the inability to selectively reduce H2O2 over O2 for commonly used stable catalysts (carbon or noble metals) is one of the key factors limiting their development and practical applications. Herein, catalysts that enable selective H2O2 reduction in the presence of oxygen with fluctuating concentrations are reported. These catalysts consist of noble metal nanoparticles underneath an amorphous chromium oxide nanolayer, which inhibits O2 diffusion to the metal/oxide interface and suppresses its reduction reaction. Using these catalysts, analytes of low concentration in biofluids, including but not limited to glucose and lactate, are detected within the presence of various interferents. This work enables wide application of the cathodic detection principle and the development of reliable noninvasive bioassays.

Functional Materials for Two‐Photon Polymerization in Microfabrication

By Marco Carlotti, Virgilio Mattoli from Wiley: Small: Table of Contents. Published on Aug 12, 2019.

Two‐photon polymerization (2PP) is a powerful tool for the on‐demand printing of precise and complex 3D architectures at the micro and nanometer scale. This Review summarizes the state‐of‐the‐art of functional resins and photoresists used in 2PP, discussing both the range of material functions available and the methods used to prepare them, highlighting advantages and disadvantages of different classes of materials in achieving certain properties. Abstract Direct laser writing methods based on two‐photon polymerization (2PP) are powerful tools for the on‐demand printing of precise and complex 3D architectures at the micro and nanometer scale. While much progress was made to increase the resolution and the feature size throughout the years, by carefully designing a material, one can confer specific functional properties to the printed structures thus making them appealing for peculiar and novel applications. This Review summarizes the state‐of‐the‐art of functional resins and photoresists used in 2PP, discussing both the range of material functions available and the methods used to prepare them, highlighting advantages and disadvantages of different classes of materials in achieving certain properties.

Ultraminiature and Flexible Sensor Based on Interior Corner Flow for Direct Pressure Sensing in Biofluids

By Longjun Tang, Wen Hong, Xiaolin Wang, Wenxi Sun, Bin Yang, Meng Wei, Jingwei Pan, Jingquan Liu from Wiley: Small: Table of Contents. Published on Aug 12, 2019.

A special capillary action, termed interior corner flow, is applied in a flexible microfluidic pressure sensor to self‐assemble the pressure‐sensitive element. Sophisticated control of capillary flow, tunable sensitivity to liquid pressure in various mediums, and multiple transduction modes are realized in this polymer device. Potential applications of this sensor include disposables for in vivo and short‐term measurements. Abstract Conventional pressure sensing devices are well developed for either indirect evaluation or internal measuring of fluid pressure over millimeter scale. Whereas, specialized pressure sensors that can directly work in various liquid environments at micrometer scale remain challenging and rarely explored, but are of great importance in many biomedical applications. Here, pressure sensor technology that utilizes capillary action to self‐assemble the pressure‐sensitive element is introduced. Sophisticated control of capillary flow, tunable sensitivity to liquid pressure in various mediums, and multiple transduction modes are realized in a polymer device, which is also flexible (thickness of 8 µm), ultraminiature (effective volume of 18 × 100 × 580 µm3), and transparent, enabling the sensor to work in some extreme situations, such as in narrow inner spaces (e.g., a microchannel of 220 µm in width and 100 µm in height), or on the surface of small objects (e.g., a 380 µm diameter needle). Potential applications of this sensor include disposables for in vivo and short‐term measurements.

Super‐Exchange Interaction Induced Overall Optimization in Ferromagnetic Perovskite Oxides Enables Ultrafast Water Oxidation

By Jie Dai, Yinlong Zhu, Yichun Yin, Hassan A. Tahini, Daqin Guan, Feifei Dong, Qian Lu, Sean C. Smith, Xiwang Zhang, Huanting Wang, Wei Zhou, Zongping Shao from Wiley: Small: Table of Contents. Published on Aug 12, 2019.

An unusual super‐exchange effect in ferromagnetic perovskite oxide is highlighted to optimize active sites and enhance electrical conductivity simultaneously. Induced by the Co (III)–O–Ru (V) super‐exchange interaction, the SrCo0.9Ru0.1O3−δ (SCR0.1) exhibits outstanding oxygen evolution reaction activity with a low overpotential of 360 mV at 10 mA cm−2 in 0.1 m KOH, which exceeds the benchmark RuO2 and most well‐known perovskites ever reported, while maintaining excellent durability. Abstract Oxygen evolution reaction (OER) is crucial in many renewable electrochemical technologies including regenerative fuel cells, rechargeable metal–air batteries, and water splitting. It is found that abundant active sites with favorable electronic structure and high electrical conductivity play a dominant role in achieving high electrocatalytic efficiency of perovskites, thus efficient strategies need to be designed to generate multiple beneficial factors for OER. Here, highlighted is an unusual super‐exchange effect in ferromagnetic perovskite oxide to optimize active sites and enhance electrical conductivity. A systematic exploration about the composition‐dependent OER activity in SrCo1x Rux O3−δ (denoted as SCRx) (x = 0.0–1.0) perovskite is displayed with special attention on the role of super‐exchange interaction between high spin (HS) Co3+ and Ru5+ ions. Induced by the unique Co3+–O–Ru5+ super‐exchange interactions, the SCR0.1 is endowed with abundant OER active species including Co3+/Co4+, Ru5+, and O22−/O−, high electrical conductivity, and metal–oxygen covalency. Benefiting from these advantageous factors for OER electrocatalysis, the optimized SCR0.1 catalyst exhibits a remarkable activity with a low overpotential of 360 mV at 10 mA cm−2, which exceeds the benchmark RuO2 and most well‐known perovskite oxides reported so far, while maintaining excellent durability. This work provides a new pathway in developing perovskite catalysts for efficient catalysis.

Anti‐VEGF‐Aptamer Modified C‐Dots—A Hybrid Nanocomposite for Topical Treatment of Ocular Vascular Disorders

By Asaf Shoval, Amos Markus, Zhixin Zhou, Xia Liu, Rémi Cazelles, Itamar Willner, Yossi Mandel from Wiley: Small: Table of Contents. Published on Aug 12, 2019.

Age‐related macular degeneration and diabetic retinopathy are macular diseases induced by the vascular endothelial growth factor (VEGF). Nontoxic anti‐VEGF aptamer‐functionalized C‐dots penetrate the cornea into the intravitreal space, where the VEGF‐driven angiogenesis is effectively inhibited. The aptamer C‐dots conjugates provide promising therapeutic materials for ocular nanomedicines. Abstract The vascular endothelial growth factor (VEGF) induces pathological angiogenetic ocular diseases. It is a scientific challenge to develop carriers for the controlled release of inhibitors for VEGF present in the back of the eye domain. Carbon dots (C‐dots) functionalized with the VEGF aptamer are introduced and the hybrid nanoparticles are used for ocular nanomedicine. The C‐dots are applied as effective carriers of the anti‐VEGF aptamer across the cornea, yielding therapeutic levels upon topical administration. The hybrids show no toxicity for both in vitro and in vivo murine animal model, and further enable noninvasive intraocular concentration monitoring through the C‐dots inherent fluorescence. In addition, the hybrid C‐dots effectively inhibit VEGF‐stimulated angiogenesis in choroidal blood vessels. This inhibition is comparable to two commercially available anti‐VEGF drugs, bevacizumab and aflibercept. The hybrid aptamer‐modified C‐dots provide a versatile nanomaterial to treat age‐related macular degeneration and diabetic retinopathy.

Photocatalytic Micromotors Activated by UV to Visible Light for Environmental Remediation, Micropumps, Reversible Assembly, Transportation, and Biomimicry

By Lei Kong, Carmen C. Mayorga‐Martinez, Jianguo Guan, Martin Pumera from Wiley: Small: Table of Contents. Published on Aug 12, 2019.

Photocatalytic micro/nanomotors (MNMs) are ultraviolet‐ or visible‐light‐induced, chemically powered MNMs based on photocatalytic materials and demonstrate potential applications in environmental remediation, micropumps, reversible assembly, transportation, and biomimicry (phototaxis). Abstract Photocatalytic micromotors are light‐induced, chemically powered micromachines based on photocatalytic materials, activated by light illumination, and have redox reactions with environmental solutions to produce chemical gradients and bubbles that propel the micromachines through self‐diffusiophoresis, self‐electrophoresis, and bubble recoil. Due to the fact that excitation light relates largely to the bandgaps of selected materials, the development of photocatalytic micromotors has experienced an evolution from ultraviolet‐light‐activated to visible‐light‐activated and potentially biocompatible systems. Furthermore, due to the strong redox capacity and physical effects caused by the products or product gradients, photocatalytic micromotors have applications in environmental remediation, micropumps, reversible assembly, transportation, and biomimicry.

Self‐Supporting, Flexible, Additive‐Free, and Scalable Hard Carbon Paper Self‐Interwoven by 1D Microbelts: Superb Room/Low‐Temperature Sodium Storage and Working Mechanism

By Bao‐Hua Hou, Ying‐Ying Wang, Qiu‐Li Ning, Wen‐Hao Li, Xiao‐Tong Xi, Xu Yang, Hao‐Jie Liang, Xi Feng, Xing‐Long Wu from Wiley: Advanced Materials: Table of Contents. Published on Aug 12, 2019.

A self‐supporting, flexible, additive‐free and scalable hard carbon paper derived from tissue is rationally developed, which achieves the outstanding Na‐storage properties in terms of high initial Coulombic efficiency (91.2%), superior high‐rate capability, ultralong cyclic stability, as well as outstanding low‐T performance in ether electrolyte. More significantly, the Na‐storage and capacity attenuation mechanism of HCP anode is revealed. Abstract Hard carbon is regarded as a promising anode material for sodium‐ion batteries (SIBs). However, it usually suffers from the issues of low initial Coulombic efficiency (ICE) and poor rate performance, severely hindering its practical application. Herein, a flexible, self‐supporting, and scalable hard carbon paper (HCP) derived from scalable and renewable tissue is rationally designed and prepared as practical additive‐free anode for room/low‐temperature SIBs with high ICE. In ether electrolyte, such HCP achieves an ICE of up to 91.2% with superior high‐rate capability, ultralong cycle life (e.g., 93% capacity retention over 1000 cycles at 200 mA g−1) and outstanding low‐temperature performance. Working mechanism analyses reveal that the plateau region is the rate‐determining step for HCP with a lower electrochemical reaction kinetics, which can be significantly improved in ether electrolyte.

Rapid Open‐Air Digital Light 3D Printing of Thermoplastic Polymer

By Shihong Deng, Jingjun Wu, Michael D. Dickey, Qian Zhao, Tao Xie from Wiley: Advanced Materials: Table of Contents. Published on Aug 12, 2019.

Digital light processing is extended from thermoset to thermoplastic polymers. The surface inhibition and the low viscosity of the resin enable the attainment of ultrafast printing under an open‐air condition. The reprocessability of the thermoplastic polymer allows its use as sacrificial molds to produce 3D functional devices from otherwise nonprintable materials. Abstract 3D printing has witnessed a new era in which highly complexed customized products become reality. Realizing its ultimate potential requires simultaneous attainment of both printing speed and product versatility. Among various printing techniques, digital light processing (DLP) stands out in its high speed but is limited to intractable light curable thermosets. Thermoplastic polymers, despite their reprocessibility that allows more options for further manipulation, are restricted to intrinsically slow printing methods such as fused deposition modeling. Extending DLP to thermoplastics is highly desirable, but is challenging due to the need to reach rapid liquid–solid separation during the printing process. Here, a successful attempt at DLP printing of thermoplastic polymers is reported, realized by controlling two competing kinetic processes (polymerization and polymer dissolution) simultaneously occurring during printing. With a selected monomer, 4‐acryloylmorpholine (ACMO), printing of thermoplastic 3D scaffolds is demonstrated, which can be further converted into various materials/devices utilizing its unique water‐soluble characteristic. The ultralow viscosity of ACMO, along with surface oxygen inhibition, allows rapid liquid flow toward high‐speed open‐air printing. The process simplicity, enabling mechanism, and material versatility broaden the scope of 3D printing in constructing functional 3D devices including reconfigurable antenna, shape‐shifting structures, and microfluidics.

[ASAP] Light-Controlled Selective Collection-and-Release of Biomolecules by an On-Chip Nanostructured Device

By Ella Borberg†#, Marina Zverzhinetsky†#, Adva Krivitsky‡, Alon Kosloff†, Omri Heifler?, Gal Degabli†, Hagit Peretz Soroka†, Ronit Satchi Fainaro‡, Larisa Burstein§, Shlomi Reuveni†, Haim Diamant†, Vadim Krivitsky*†, and Fernando Patolsky*†? from Nano Letters: Latest Articles (ACS Publications). Published on Aug 12, 2019.

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Nano Letters
DOI: 10.1021/acs.nanolett.9b01323

[ASAP] Theory of Spin Hall Magnetoresistance from a Microscopic Perspective

By Xian-Peng Zhang†‡, F. Sebastian Bergeret†‡, and Vitaly N. Golovach*†‡§? from Nano Letters: Latest Articles (ACS Publications). Published on Aug 12, 2019.

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Nano Letters
DOI: 10.1021/acs.nanolett.9b02459

[ASAP] Hierarchical Hybridization in Plasmonic Honeycomb Lattices

By Ran Li†?, Marc R. Bourgeois‡?, Charles Cherqui‡?, Jun Guan§, Danqing Wang§, Jingtian Hu†, Richard D. Schaller‡?, George C. Schatz*‡§, and Teri W. Odom*†‡§ from Nano Letters: Latest Articles (ACS Publications). Published on Aug 12, 2019.

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Nano Letters
DOI: 10.1021/acs.nanolett.9b02661

[ASAP] Exchange Rules for Diradical p-Conjugated Hydrocarbons

By Ricardo Ortiz*†‡?, Roberto A. Boto§, Noel Garci´a-Marti´nez†‡, Juan C. Sancho-Garci´a?, Manuel Melle-Franco§, and Joaqui´n Ferna´ndez-Rossier† from Nano Letters: Latest Articles (ACS Publications). Published on Aug 12, 2019.

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Nano Letters
DOI: 10.1021/acs.nanolett.9b01773

[ASAP] Intracellularly Generated Immunological Gold Nanoparticles for Combinatorial Photothermal Therapy and Immunotherapy against Tumor

By Dan Zhang†‡, Tingting Wu†§, Xianya Qin†, Qi Qiao†, Lihuan Shang†, Qingle Song†, Conglian Yang†, and Zhiping Zhang*†?? from Nano Letters: Latest Articles (ACS Publications). Published on Aug 12, 2019.

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Nano Letters
DOI: 10.1021/acs.nanolett.9b02903

[ASAP] High-Resolution Imaging of Maltoporin LamB while Quantifying the Free-Energy Landscape and Asymmetry of Sugar Binding

By Estefania Mulvihill, Moritz Pfreundschuh, Johannes Thoma, Noah Ritzmann, and Daniel J. Mu¨ller* from Nano Letters: Latest Articles (ACS Publications). Published on Aug 12, 2019.

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Nano Letters
DOI: 10.1021/acs.nanolett.9b02674

[ASAP] Ultrasensitive Three-Dimensional Orientation Imaging of Single Molecules on Plasmonic Nanohole Arrays Using Second Harmonic Generation

By Sushant P. Sahu†?, Amirreza Mahigir‡§?, Benjamin Chidester?, Georgios Veronis‡§, and Manas Ranjan Gartia*† from Nano Letters: Latest Articles (ACS Publications). Published on Aug 12, 2019.

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Nano Letters
DOI: 10.1021/acs.nanolett.9b02239

[ASAP] Tunable Coupling of a Double Quantum Dot Spin System to a Mechanical Resonator

By Samuel G. Carter*†, Allan S. Bracker†, Michael K. Yakes†, Maxim K. Zalalutdinov†, Mijin Kim‡, Chul Soo Kim†, Bumsu Lee§, and Daniel Gammon† from Nano Letters: Latest Articles (ACS Publications). Published on Aug 12, 2019.

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Nano Letters
DOI: 10.1021/acs.nanolett.9b02207

[ASAP] Avidity and Cell Uptake of Integrin-Targeting Polypeptide Micelles is Strongly Shape-Dependent

By Michael Dzuricky†, Sinan Xiong†, Patrick Weber†‡, and Ashutosh Chilkoti*† from Nano Letters: Latest Articles (ACS Publications). Published on Aug 12, 2019.

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Nano Letters
DOI: 10.1021/acs.nanolett.9b02095

[ASAP] pH-Dependent Distribution of Functional Groups on Titanium-Based MXenes

By Rina Ibragimova, Martti J. Puska, and Hannu-Pekka Komsa* from ACS Nano: Latest Articles (ACS Publications). Published on Aug 12, 2019.

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ACS Nano
DOI: 10.1021/acsnano.9b03511

[ASAP] Carbon Nitride Transforms into a High Lithium Storage Capacity Nitrogen-Rich Carbon

By Joshua P. Pender†, Joseph V. Guerrera†, Bryan R. Wygant†, Jason A. Weeks†, Ryan A. Ciufo†, James N. Burrow‡, Mitchell F. Walk‡, Mohammad Z. Rahman‡, Adam Heller‡, and C. Buddie Mullins*†‡ from ACS Nano: Latest Articles (ACS Publications). Published on Aug 12, 2019.

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ACS Nano
DOI: 10.1021/acsnano.9b03861

[ASAP] Fast Energy Storage in Two-Dimensional MoO2 Enabled by Uniform Oriented Tunnels

By Yuanyuan Zhu†?, Xu Ji‡?, Shuang Cheng*†, Zhao-Ying Chern?, Jin Jia#, Lufeng Yang§, Haowei Luo†, Jiayuan Yu†, Xinwen Peng†, Jenghan Wang?, Weijia Zhou*†#, and Meilin Liu*§ from ACS Nano: Latest Articles (ACS Publications). Published on Aug 12, 2019.

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ACS Nano
DOI: 10.1021/acsnano.9b03324

[ASAP] Controllably Enriched Oxygen Vacancies through Polymer Assistance in Titanium Pyrophosphate as a Super Anode for Na/K-Ion Batteries

By Zhongtao Li*, Yunfa Dong, Jianze Feng, Tao Xu, Hao Ren, Cai Gao, Yueran Li, Mingjie Cheng, Wenting Wu, and Mingbo Wu* from ACS Nano: Latest Articles (ACS Publications). Published on Aug 12, 2019.

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ACS Nano
DOI: 10.1021/acsnano.9b03686

[ASAP] Self-Healing Nanophotonics: Robust and Soft Random Lasers

By Yun-Tzu Hsu†, Chia-Tse Tai†, Hsing-Mei Wu‡, Cheng-Fu Hou?, Yu-Ming Liao†, Wei-Cheng Liao†, Golam Haider†, Yung-Chi Hsiao‡, Chi-Wei Lee?, Shu-Wei Chang†, Ying-Huan Chen†, Min-Hsuan Wu†, Rou-Jun Chou†, Krishna Prasad Bera†, Yen-Yu Lin†, Yi-Zih Chen†, Monika Kataria†, Shih-Yao Lin†, Christy Roshini Paul Inbaraj†, Wei-Ju Lin†, Wen-Ya Lee?, Tai-Yuan Lin?, Ying-Chih Lai*‡§, and Yang-Fang Chen*† from ACS Nano: Latest Articles (ACS Publications). Published on Aug 12, 2019.

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ACS Nano
DOI: 10.1021/acsnano.9b02858

[ASAP] Plasmon-Induced Electron–Hole Separation at the Ag/TiO2(110) Interface

By Jie Ma*† and Shiwu Gao*‡ from ACS Nano: Latest Articles (ACS Publications). Published on Aug 12, 2019.

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ACS Nano
DOI: 10.1021/acsnano.9b03555

[ASAP] Water-Dispersed High-Quality Graphene: A Green Solution for Efficient Energy Storage Applications

By Zhaoyang Liu†, Heng Zhang‡, Matilde Eredia†, Haixin Qiu†, Walid Baaziz§, Ovidiu Ersen§, Artur Ciesielski*†, Mischa Bonn‡, Hai I. Wang‡, and Paolo Samori`*† from ACS Nano: Latest Articles (ACS Publications). Published on Aug 12, 2019.

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ACS Nano
DOI: 10.1021/acsnano.9b04232

[ASAP] Biomimetic Superoxide Disproportionation Catalyst for Anti-Aging Lithium–Oxygen Batteries

By Chihyun Hwang†§, JongTae Yoo‡§, Gwan Yeong Jung†§, Se Hun Joo†, Jonghak Kim†, Aming Cha†, Jung-Gu Han†, Nam-Soon Choi†, Seok Ju Kang†, Sang-Young Lee†, Sang Kyu Kwak*†?, and Hyun-Kon Song*†? from ACS Nano: Latest Articles (ACS Publications). Published on Aug 12, 2019.

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ACS Nano
DOI: 10.1021/acsnano.9b03525

[ASAP] In Situ Electron Microscopy Investigation of Sodiation of Titanium Disulfide Nanoflakes

By Xiuzhen Wang†‡?, Zhenpeng Yao#?, Sooyeon Hwang‡, Ying Pan¶, Hui Dong?, Maosen Fu§, Na Li?‡, Ke Sun‡, Hong Gan‡, Yan Yao?, Ala´n Aspuru-Guzik#¦??, Qingyu Xu*†, and Dong Su*‡ from ACS Nano: Latest Articles (ACS Publications). Published on Aug 12, 2019.

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ACS Nano
DOI: 10.1021/acsnano.9b04222

[ASAP] Synthesis and Magnetism of Neutral, Linear Metallocene Complexes of Terbium(II) and Dysprosium(II)

By Colin A. Gould†§, K. Randall McClain‡§, Jason M. Yu¶, Thomas J. Groshens‡, Filipp Furche*¶, Benjamin G. Harvey*‡, and Jeffrey R. Long*†?? from Journal of the American Chemical Society: Latest Articles (ACS Publications). Published on Aug 12, 2019.

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Journal of the American Chemical Society
DOI: 10.1021/jacs.9b05816

Guiding of visible photons at the ångström thickness limit

By Ertugrul Cubukcu from Nature Nanotechnology - Issue - nature.com science feeds. Published on Aug 12, 2019.

Nature Nanotechnology, Published online: 12 August 2019; doi:10.1038/s41565-019-0519-6

A monolayer WS2 membrane patterned as a photonic crystal sustains guided optical modes that propagate via total internal reflection.

Dispersing nanoparticles into single atoms

By Abhaya K. Datye from Nature Nanotechnology - Issue - nature.com science feeds. Published on Aug 12, 2019.

Nature Nanotechnology, Published online: 12 August 2019; doi:10.1038/s41565-019-0513-z

While heating a catalyst causes growth of nanoparticles through Ostwald ripening, repeated on/off high-temperature shockwaves can reverse the process, converting the nanoparticles into stable single-atom catalysts.

High temperature shockwave stabilized single atoms

By Liangbing Hu from Nature Nanotechnology - Issue - nature.com science feeds. Published on Aug 12, 2019.

Nature Nanotechnology, Published online: 12 August 2019; doi:10.1038/s41565-019-0518-7

A repeated on–off high-temperature shockwave is shown to be a generalizable way of efficiently synthesizing and stabilizing single atoms at high temperatures.

Nanometre-thin indium tin oxide for advanced high-performance electronics

By Yanqing Wu from Nature Materials - Issue - nature.com science feeds. Published on Aug 12, 2019.

Nature Materials, Published online: 12 August 2019; doi:10.1038/s41563-019-0455-8

Controlled physical vapour deposition of indium tin oxide layers with thickness down to 4 nm allows the use of these materials as active channels in high-performing transistors for digital and radiofrequency electronics.

Self-assembled nanostructures in ionic liquids facilitate charge storage at electrified interfaces

By T. Alan Hatton from Nature Materials - Issue - nature.com science feeds. Published on Aug 12, 2019.

Nature Materials, Published online: 12 August 2019; doi:10.1038/s41563-019-0449-6

Understanding molecular interactions between ionic liquids and interfaces is crucial for electrochemical device applications. Self-assembled amphiphilic nanostructures in surface-active ionic liquids are shown to exhibit enhanced charge storage at electrified surfaces.

Spin chirality fluctuation in two-dimensional ferromagnets with perpendicular magnetic anisotropy

By Weida Wu from Nature Materials - Issue - nature.com science feeds. Published on Aug 12, 2019.

Nature Materials, Published online: 12 August 2019; doi:10.1038/s41563-019-0454-9

Evidence for spin chirality fluctuations in two-dimensional ferromagnets is provided by magnetotransport measurements.

Phonon transport across crystal-phase interfaces and twin boundaries in semiconducting nanowires

By Riccardo Rurali from RSC - Nanoscale latest articles. Published on Aug 12, 2019.

Nanoscale, 2019, Advance Article
DOI: 10.1039/C9NR05274G, Paper
Jesús Carrete, Miquel López-Suárez, Martí Raya-Moreno, Anton S. Bochkarev, Miquel Royo, Georg K. H. Madsen, Xavier Cartoixà, Natalio Mingo, Riccardo Rurali
We combine state-of-the-art Green's-function methods and nonequilibrium molecular dynamics calculations to study phonon transport across the unconventional interfaces that make up crystal-phase and twinning superlattices in nanowires.
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In situ Self‐Assembled Nanofibers Precisely Position Cancer Associated Fibroblasts for Improved Tumor Imaging

By Hao Wang, Xiao-Xiao Zhao, Li-Li Li, Ying Zhao, Hong-Wei An, Qian Cai, Jia-Yan Lang, Xue-Xiang Han, Bo Peng, Yue Fei, Hao Liu, Hao Qin, Guangjun Nie from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 11, 2019.

The tumor complexity makes the development of high sensitive tumor imaging probes facing arduous tasks. Here, we construct a fibroblast activation protein‐α (FAP‐α) responsive peptide‐based near infrared probe, which specifically in situ forms nanofibers on the surface of cancer associated fibroblasts (CAFs). The assembly/aggregation induced retention (AIR) effect endows the probe enhanced accumulation and retention around the tumor, resulting in 5.5‐fold signal enhancement in tumor compared to that of the non‐aggregatable control molecule post 24 h administration through ex vivo imaging. This probe provides a prolonged detectable windows over 48 h for tumor diagnosis. Meanwhile, the selective assembly of the probe widen the difference of accumulation in tumor and in metabolic organ (e.g. liver and kidney) resulting over 4‐fold and 5‐fold higher signal intensity in tumor than that of liver and kidney, respectively. With enhanced tumor imaging capability, this probe can visualize small tumors around 2 mm in diameter. We believe that our imaging strategy may offer a powerful tumor bioimaging approach with high specificity and sensitivity.

Palladium Mediated Cleavage of Thiazolidine Backbone Modified Proteins in Live Cells

By Ashraf Brik, Guy Mann, Gandhesiri Satish, Roman Meledin, Ganga B. Vamisetti from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 11, 2019.

Chemical protein synthesis and biorthogonal modification chemistries allow production of unique proteins for a range of biological studies. Bond forming reactions for site‐selective protein labeling are commonly used in these endeavors. Selective bond cleavage reactions, however, are much less explored and still pose a great challenge. In addition, most of studies with modified proteins prepared by total synthesis or semisynthetically have been applied mainly for in vitro experiments with very limited extension to live cells. Here, we report an approach for studying uniquely modified proteins containing a traceless cell delivery unit and palladium‐based cleavable element for chemical activation activation and monitoring the effect of these proteins in live cells. We demonstrated this approach in the synthesis of caged ubiquitin‐aldehyde, which was decaged for the inhibition of deubiquitinases in live cells.

Bamboo‐Like Nitrogen‐Doped Carbon Nanotube Forests as Durable Metal‐Free Catalysts for Self‐Powered Flexible Li–CO2 Batteries

By Xuelian Li, Jingwen Zhou, Junxiang Zhang, Matthew Li, Xuanxuan Bi, Tongchao Liu, Tao He, Jianli Cheng, Fan Zhang, Yongpeng Li, Xiaowei Mu, Jun Lu, Bin Wang from Wiley: Advanced Materials: Table of Contents. Published on Aug 09, 2019.

A self‐powered fiber‐shaped Li–CO2 battery with overall photochemical–electric energy conversion efficiency of up to 4.6% is fabricated using bifunctional bamboo‐like N‐doped carbon nanotube fiber as cathodes for Li–CO2 batteries and as counter electrodes for dye‐sensitized solar cells simultaneously. The fiber‐shaped Li–CO2 batteries show high specific capacity, long cycle life, and high flexibility. Abstract The Li–CO2 battery is a promising energy storage device for wearable electronics due to its long discharge plateau, high energy density, and environmental friendliness. However, its utilization is largely hindered by poor cyclability and mechanical rigidity due to the lack of a flexible and durable catalyst electrode. Herein, flexible fiber‐shaped Li–CO2 batteries with ultralong cycle‐life, high rate capability, and large specific capacity are fabricated, employing bamboo‐like N‐doped carbon nanotube fiber (B‐NCNT) as flexible, durable metal‐free catalysts for both CO2 reduction and evolution reactions. Benefiting from high N‐doping with abundant pyridinic groups, rich defects, and active sites of the periodic bamboo‐like nodes, the fabricated Li–CO2 battery shows outstanding electrochemical performance with high full‐discharge capacity of 23 328 mAh g−1, high rate capability with a low potential gap up to 1.96 V at a current density of 1000 mA g−1, stability over 360 cycles, and good flexibility. Meanwhile, the bifunctional B‐NCNT is used as the counter electrode for a fiber‐shaped dye‐sensitized solar cell to fabricate a self‐powered fiber‐shaped Li–CO2 battery with overall photochemical–electric energy conversion efficiency of up to 4.6%. Along with a stable voltage output, this design demonstrates great adaptability and application potentiality in wearable electronics with a breath monitor as an example.

What Is XNA?

By John C. Chaput, Piet Herdewijn from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

X files: The term “xeno‐nucleic acids” (XNA) has grown in popularity to the point that it has become a catch‐all phrase for almost any unnatural nucleic acid, raising the question: what is XNA and how does it differ from chemically modified DNA? Abstract The term “xeno‐nucleic acids”, abbreviated XNA, has grown in popularity to the point that it has become a catch‐all phrase for almost any unnatural nucleic acid, raising the question: what is XNA and how does it differ from chemically modified DNA?

Deutsche Bunsengesellschaft Awards

By from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Hans Herbert Brintzinger (1935–2019)

By John Bercaw, Heinz Berke, Stefan Mecking from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Graphical Abstract: Angew. Chem. Int. Ed. 34/2019

By from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Back Cover: [Am(C5Me4H)3]: An Organometallic Americium Complex (Angew. Chem. Int. Ed. 34/2019)

By Conrad A. P. Goodwin, Jing Su, Thomas E. Albrecht‐Schmitt, Anastasia V. Blake, Enrique R. Batista, Scott R. Daly, Stefanie Dehnen, William J. Evans, Andrew J. Gaunt, Stosh A. Kozimor, Niels Lichtenberger, Brian L. Scott, Ping Yang from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Organometallic americium synthetic chemistry has been dormant for decades. Now, E. R. Batista, W. J. Evans, A. J. Gaunt, S. A. Kozimor, P. Yang et al. report the crystallographically characterized complex [Am(C5Me4H)3], featuring the first quantitative measurement of Am−C molecular bonding interactions. In their Communication on page 11695 ff., spectroscopic comparison with ab initio calculations reveal a 5f6 electronic configuration, and the 5f→5f/5f→6d transitions are accurately assigned. Graphic designed by Mr. Josh Smith, Chemistry Division, Los Alamos National Laboratory.

Cover Picture: Elucidating the Doping Effect on the Electronic Structure of Thiolate‐Protected Silver Superatoms by Photoelectron Spectroscopy (Angew. Chem. Int. Ed. 34/2019)

By Kuenhee Kim, Keisuke Hirata, Katsunosuke Nakamura, Hirokazu Kitazawa, Shun Hayashi, Kiichirou Koyasu, Tatsuya Tsukuda from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Doping with heteroatoms is a promising strategy to tune and improve the properties of thiolate‐protected silver superatoms. By using gas‐phase photoelectron spectroscopy, T. Tsukuda and co‐workers reveal in their Communication on page 11637 that substitution of the central X+ cation in [XAg24(SR)18]− (X=Ag, Au) by a neutral Pd or Pt atom leads to an energy shift of the superatomic 1P orbitals by about 1.4 eV.

Frontispiece: Catalytic Ammonia Oxidation to Dinitrogen by Hydrogen Atom Abstraction

By Papri Bhattacharya, Zachariah M. Heiden, Geoffrey M. Chambers, Samantha I. Johnson, R. Morris Bullock, Michael T. Mock from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Ammonia Oxidation A molecular Ru‐based catalyst converts NH3 into N2, as reported by M. T. Mock et al. in their Communication on page 11618. The cleavage of six N−H bonds was achieved by coupling H+ and e− transfers using the tBu3ArO. radical as the H atom acceptor.

Inside Cover: Paramagnetic Carbon Nanosheets with Random Hole Defects and Oxygenated Functional Groups (Angew. Chem. Int. Ed. 34/2019)

By Sun‐Min Jung, Jungmin Park, Dongbin Shin, Hu Young Jeong, DongKyu Lee, In‐Yup Jeon, HyungJoon Cho, Noejung Park, Jung‐Woo Yoo, Jong‐Beom Baek from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Ordered graphitic carbon nanosheets (GCNs) were synthesized by the direct condensation of multifunctional phenylacetyl monomers in the presence of phosphorus pentoxide. J.‐B. Baek et al. show in their Communication on page 11670 ff. that the GCNs had an aligned hexagonal carbon lattice with nanosized random hole defects and oxygenated functional groups. Their structure generated and stabilized spins in GCNs, inducing paramagnetism.

Inside Back Cover: A Solid‐State Protein Junction Serves as a Bias‐Induced Current Switch (Angew. Chem. Int. Ed. 34/2019)

By Jerry A. Fereiro, Ben Kayser, Carlos Romero‐Muñiz, Ayelet Vilan, Dmitry A. Dolgikh, Rita V. Chertkova, Juan Carlos Cuevas, Linda A. Zotti, Israel Pecht, Mordechai Sheves, David Cahen from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

An electrically driven switch can be formed by a cytochrome C monolayer, sandwiched between a gold layer and a gold nanowire, as reported by D. Cahen et al. in their Communication on page 11852 ff. The charge‐transport mechanism of cytochrome C can be switched between on‐ and off‐resonant tunneling by varying the applied voltage bias, even at room temperature. This is an important step towards protein‐based electronics.

Electron‐Deficient Triborane and Tetraborane Ring Compounds: Synthesis, Structure, and Bonding

By Hans‐Jörg Himmel from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Living with a deficit: Small boron rings have a strong affection for σ‐ and π‐delocalization and are tolerant of various skeletal electron numbers. This Review gives a comprehensive overview of the synthesis and electronic structures of electron‐deficient B3 and B4 ring compounds. Abstract Electron‐deficient small boron rings are unique in their formation of σ‐ and π‐delocalized electron systems as well as the avoidance of “classical” structures with two‐center‐two‐electron (2c,2e) bonds. These rings are tolerant of several skeletal electron numbers, which makes their redox chemistry highly interesting. In the past few decades, a range of stable compounds have been synthesized with various electron numbers in their B3 and B4 cores. The electronic structures were evaluated by quantum‐chemical calculations. On the other hand, the chemistry of these rings is still very much underdeveloped, being generally limited to the protonation and redox reactions of individual systems. The linkage of several B3 and/or B4 ring systems should give compounds with attractive electronic properties, thus leading the way to novel boron‐based materials. By summarizing important experimental and theoretical results, this Review intends to provide the basis for the exploration of the chemistry of these rings and, in particular, their integration into larger molecular architectures.

In Situ Amplification‐Based Imaging of RNA in Living Cells

By Zhihe Qing, Jingyuan Xu, Jinlei Hu, Jing Zheng, Lei He, Zhen Zou, Sheng Yang, Weihong Tan, Ronghua Yang from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

RNA imaging: In recent years, the advance of isothermal amplification technologies for nucleic acids has opened paths for the amplified imaging of RNAs in living cells. This Minireview tracks the development of in situ amplification assays of RNAs in living cells, and highlights the potential challenges facing this field. Abstract Owing to its important physiological functions, especially as molecular biomarkers of diseases, RNA is an important focus of biomedicine and biochemical sensing. Signal amplification detection has been put forward because of the need for accurate identification of RNA at low expression levels, which is significant for the early diagnosis and therapy of malignant diseases. However, conventional amplification methods for RNA analysis depend on the use of enzymes, fixation of cells, and thermal cycling, which confine their performance to cell lysates or dead cells, thus the imaging of RNA in living cells remained until recently little explored. In recent years, the advance of isothermal amplification of nucleic acids has opened paths for meeting this need in living cells. This minireview tracks the development of in situ amplification assays for RNAs in living cells, and highlights the potential challenges facing this field, aiming to improve the development of in vivo isothermal amplification as well as usher in new frontiers in this fertile research area.

Catalysis with Palladium Complexes Photoexcited by Visible Light

By Padon Chuentragool, Daria Kurandina, Vladimir Gevorgyan from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Making light of catalysis: In contrast to classical reactions catalyzed by Pd complexes in the ground state, which mostly proceed through two‐electron redox processes, the mechanisms of the methods based on the photoexcitation of Pd usually operate through transfer of a single electron. This Minireview highlights the recent progress in this rapidly emerging area of Pd catalysis induced by visible light. Abstract Palladium catalysis induced by visible light is an emerging field of catalysis. In contrast to classical reactions catalyzed by Pd complexes in the ground state, which mostly proceed through two‐electron redox processes, the mechanisms of these new methods based on photoexcited Pd complexes usually operate through transfer of a single electron. Such processes lead to putative hybrid Pd/radical species, which exhibit both radical and classical Pd‐type reactivity. This Minireview highlights the recent progress in this rapidly growing area.

Asymmetric Catalytic Formal 1,4‐Allylation of β,γ‐Unsaturated α‐Ketoesters: Allylboration/Oxy‐Cope Rearrangement

By Qiong Tang, Kai Fu, Peiran Ruan, Shunxi Dong, Zhishan Su, Xiaohua Liu, Xiaoming Feng from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

A highly efficient catalytic asymmetric allylboration/oxy‐Cope rearrangement reaction sequence of β,γ‐unsaturated α‐ketoesters with allylboronic acids has been realized by employing a NiII/N,N′‐dioxide complex as the catalyst. This transformation provides a facile and rapid route to formal allyl conjugate addition products, chiral γ‐allyl‐α‐ketoesters, with good results. Abstract A highly enantioselective formal conjugate allyl addition of allylboronic acids to β,γ‐unsaturated α‐ketoesters has been realized by employing a chiral NiII/N,N′‐dioxide complex as the catalyst. This transformation proceeds by an allylboration/oxy‐Cope rearrangement sequence, providing a facile and rapid route to γ‐allyl‐α‐ketoesters with moderate to good yields (65–92 %) and excellent ee values (90–99 % ee). The isolation of 1,2‐allylboration products provided insight into the mechanism of the subsequent oxy‐Cope rearrangement reaction: substrate‐induced chiral transfer and a chiral Lewis acid accelerated process. Based on the experimental investigations and DFT calculations, a rare boatlike transition‐state model is proposed as the origin of high chirality transfer during the oxy‐Cope rearrangement.

General π‐Electron‐Assisted Strategy for Ir, Pt, Ru, Pd, Fe, Ni Single‐Atom Electrocatalysts with Bifunctional Active Sites for Highly Efficient Water Splitting

By Wei‐Hong Lai, Li‐Fu Zhang, Wei‐Bo Hua, Sylvio Indris, Zi‐Chao Yan, Zhe Hu, Binwei Zhang, Yani Liu, Li Wang, Min Liu, Rong Liu, Yun‐Xiao Wang, Jia‐Zhao Wang, Zhenpeng Hu, Hua‐Kun Liu, Shu‐Lei Chou, Shi‐Xue Dou from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

HER and OER! The hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) are crucial to water splitting, but require alternative active sites. Now, a general π‐electron‐assisted strategy to anchor single‐atom sites (M=Ir, Pt, Ru, Pd, Fe, Ni) on a heterogeneous support is reported. The M atoms can simultaneously anchor on two distinct domains of the hybrid support, four‐fold N/C atoms, and centers of Co octahedra. Abstract Both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) are crucial to water splitting, but require alternative active sites. Now, a general π‐electron‐assisted strategy to anchor single‐atom sites (M=Ir, Pt, Ru, Pd, Fe, Ni) on a heterogeneous support is reported. The M atoms can simultaneously anchor on two distinct domains of the hybrid support, four‐fold N/C atoms (M@NC), and centers of Co octahedra (M@Co), which are expected to serve as bifunctional electrocatalysts towards the HER and the OER. The Ir catalyst exhibits the best water‐splitting performance, showing a low applied potential of 1.603 V to achieve 10 mA cm−2 in 1.0 m KOH solution with cycling over 5 h. DFT calculations indicate that the Ir@Co (Ir) sites can accelerate the OER, while the Ir@NC3 sites are responsible for the enhanced HER, clarifying the unprecedented performance of this bifunctional catalyst towards full water splitting.

Metal‐Free Oxidative B−N Coupling of nido‐Carborane with N‐Heterocycles

By Zhongming Yang, Weijia Zhao, Wei Liu, Xing Wei, Meng Chen, Xiao Zhang, Xiaolei Zhang, Yong Liang, Changsheng Lu, Hong Yan from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

The metal‐free B−N coupling of nido‐carboranes with various N‐heterocycles was studied. Both inter‐ and intramolecular reactions occur at ambient temperature, with high to excellent yields and high atom economy. DDQ=2,3‐dichloro‐5,6‐dicyanobenzoquinone, DME=1,2‐dimethoxyethane. Abstract A general method for the oxidative substitution of nido‐carborane (7,8‐C2B9H12−) with N‐heterocycles has been developed by using 2,3‐dichloro‐5,6‐dicyanobenzoquinone (DDQ) as an oxidant. This metal‐free B−N coupling strategy, in both inter‐ and intramolecular fashions, gave rise to a wide array of charge‐compensated, boron‐substituted nido‐carboranes in high yields (up to 97 %) with excellent functional‐group tolerance under mild reaction conditions. The reaction mechanism was investigated by density‐functional theory (DFT) calculations. A successive single‐electron transfer (SET), B−H hydrogen‐atom transfer (HAT), and nucleophilic attack pathway is proposed. This method provides a new approach to nitrogen‐containing carboranes with potential applications in medicine and materials.

Resolving Optical and Catalytic Activities in Thermoresponsive Nanoparticles by Permanent Ligation with Temperature‐Sensitive Polymers

By Yihuang Chen, Zewei Wang, Yeu Wei Harn, Shuang Pan, Zili Li, Shaoliang Lin, Juan Peng, Guangzhao Zhang, Zhiqun Lin from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Star‐shaped: A general strategy leads to the creation of permanently ligated thermoresponsive nanoparticles with tunable dimensions and compositions by utilizing a rationally designed starlike diblock copolymer (PNIPAM) as a nanoreactor. Studies of the nanoparticles, showing two seemingly contradictory observations on both temperature‐dependent optical and catalytic properties, have led to the reconciliation of data. LCST=lower critical solution temperature. Abstract Thermoresponsive nanoparticles (NPs) represent an important hybrid material comprising functional NPs with temperature‐sensitive polymer ligands. Strikingly, significant discrepancies in optical and catalytic properties of thermoresponsive noble‐metal NPs have been reported, and have yet to be unraveled. Reported herein is the crafting of Au NPs, intimately and permanently ligated by thermoresponsive poly(N‐isopropylacrylamide) (PNIPAM), in situ using a starlike block copolymer nanoreactor as model system to resolve the paradox noted above. As temperature rises, plasmonic absorption of PNIPAM‐capped Au NPs red‐shifts with increased intensity in the absence of free linear PNIPAM, whereas a greater red‐shift with decreased intensity occurs in the presence of deliberately introduced linear PNIPAM. Remarkably, the absence or addition of free linear PNIPAM also accounts for non‐monotonic or switchable on/off catalytic performance, respectively, of PNIPAM‐capped Au NPs.

A Cyclopropene Electrophile that Targets Glutathione S‐Transferase Omega‐1 in Cells

By Gustav J. Wørmer, Bente K. Hansen, Johan Palmfeldt, Thomas B. Poulsen from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Reactriangle: The first example of a cyclopropene with covalent reactivity in cells is presented. The probe reacts with thiols in vitro through fragmentation of the cyclopropene‐ring and alkylates the active‐site cysteine of glutathione S‐transferase omega‐1 in cells. Abstract Cyclopropenes are an important new addition to the portfolio of functional groups that can be used for bioorthogonal couplings. The inert nature of these highly strained compounds in complex biological systems is almost counterintuitive given their established electrophilic properties in organic synthesis. Here we provide the first demonstration of a cyclopropene that is capable of direct conjugation to protein targets in cells and show that this compound preferentially alkylates the active site cysteine of glutathione S‐transferase omega‐1 (GSTO1).

Significant Difference in Semiconducting Properties of Isomeric All‐Acceptor Polymers Synthesized via Direct Arylation Polycondensation

By Yang Wang, Tsukasa Hasegawa, Hidetoshi Matsumoto, Tsuyoshi Michinobu from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Two isomeric all‐acceptor copolymers are synthesized by a new direct arylation polycondensation route. The isomerism affects the optoelectronic, molecular packing, and electron transporting properties. The highly crystalline isomer polymer P2 produces highly stable transistors with the excellent electron mobility of 2.55 cm2 V−1 s−1. Abstract The direct arylation polycondensation (DArP) appeared as an efficient method for producing semiconducting polymers but often requires acceptor monomers with orienting or activating groups for the reactive carbon‐hydrogen (C‐H) bonds, which limits the choice of acceptor units. In this study, we describe a DArP for producing high‐molecular‐weight all‐acceptor polymers composed of the acceptor monomers without any orienting or activating groups via a modified method using Pd/Cu co‐catalysts. We thus obtained two isomeric all‐acceptor polymers, P1 and P2, which have the same backbone and side‐chains but different positions of the nitrogen atoms in the thiazole units. This subtle change significantly influences their optoelectronic, molecular packing, and charge‐transport properties. P2 with a greater backbone torsion has favorable edge‐on orientations and a high electron mobility μe of 2.55 cm2 V−1 s−1. Moreover, P2‐based transistors show an excellent shelf‐storage stability in air even after the storage for 1 month.

Mercury Cyanides and Isocyanides: NCHgCN and CNHgNC as well as NCHgHgCN and CNHgHgNC: Simple Molecules with Short, Strong Hg−Hg Bonds

By Lester Andrews, Han‐Gook Cho from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Mercury atoms react with cyanogen in excess argon at 4 K to give four major products. Shown is a CCSD plot of the occupied 6s σ‐bonding molecular orbital (HOMO‐1) for the single bond in the NCHg−HgCN product. Abstract Mercury atoms, laser‐ablated from an amalgam dental filling target, react with cyanogen in excess argon during condensation at 4 K to form two major products in the 2200 cyanide M−C−N stretching region of the IR spectrum, which were assigned to NCHgCN and NCHgHgCN from their antisymmetric C−N stretching mode absorptions at 2213.8 and 2180.1 cm−1. Two broader bands in the isocyanide region at 2098.2 and 2089.6 cm−1 were assigned to CNHgNC and CNHgHgNC. The N‐bonded isomers were computed to be 603/33 and 823/69 times more intense IR absorbers than the C‐bonded isomers at the CCSD level of theory. The dissociation energy for the NCHg−HgCN molecule into two HgCN molecules was calculated to be 296 kJ mol−1 and that for CNHg−HgNC into two HgNC molecules is 304 kJ mol−1. These simple molecules with two cyanide or two isocyanide ligands have two of the shortest and strongest known Hg−Hg single bonds as the two electronegative CN ligands withdraw antibonding electron density from the bonding region.

A Solid‐State Protein Junction Serves as a Bias‐Induced Current Switch

By Jerry A. Fereiro, Ben Kayser, Carlos Romero‐Muñiz, Ayelet Vilan, Dmitry A. Dolgikh, Rita V. Chertkova, Juan Carlos Cuevas, Linda A. Zotti, Israel Pecht, Mordechai Sheves, David Cahen from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Down to the wire: A cytochrome C monolayer, attached to a Au layer using S−Au bonding, and coated with a Au nanowire, can behave as an electrically driven switch. The charge‐transport mechanism of cytochrome C can be switched between on‐and off‐resonant tunneling by varying the applied voltage bias, even at room temperature. This is an important step towards protein‐based electronics. Abstract A sample‐type protein monolayer, that can be a stepping stone to practical devices, can behave as an electrically driven switch. This feat is achieved using a redox protein, cytochrome C (CytC), with its heme shielded from direct contact with the solid‐state electrodes. Ab initio DFT calculations, carried out on the CytC–Au structure, show that the coupling of the heme, the origin of the protein frontier orbitals, to the electrodes is sufficiently weak to prevent Fermi level pinning. Thus, external bias can bring these orbitals in and out of resonance with the electrode. Using a cytochrome C mutant for direct S−Au bonding, approximately 80 % of the Au–CytC–Au junctions show at greater than 0.5 V bias a clear conductance peak, consistent with resonant tunneling. The on–off change persists up to room temperature, demonstrating reversible, bias‐controlled switching of a protein ensemble, which, with its built‐in redundancy, provides a realistic path to protein‐based bioelectronics.

Utilizing the Space‐Charge Region of the FeNi‐LDH/CoP p‐n Junction to Promote Performance in Oxygen Evolution Electrocatalysis

By Kai He, Tsegaye Tadesse Tsega, Xi Liu, Jiantao Zai, Xin‐Hao Li, Xuejiao Liu, Wenhao Li, Nazakat Ali, Xuefeng Qian from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

The p‐n junction in FeNi‐LDH/CoP with positively charged FeNi‐LDH in the space‐charge region exhibits superior electro‐catalytical activity for the oxygen evolution reaction (OER). LDH=layered double hydroxide. Abstract The modulation of electron density is an effective option for efficient alternative electrocatalysts. Here, p‐n junctions are constructed in 3D free‐standing FeNi‐LDH/CoP/carbon cloth (CC) electrode (LDH=layered double hydroxide). The positively charged FeNi‐LDH in the space‐charge region can significantly boost oxygen evolution reaction. Therefore, the j at 1.485 V (vs. RHE) of FeNi‐LDH/CoP/CC achieves ca. 10‐fold and ca. 100‐fold increases compared to those of FeNi‐LDH/CC and CoP/CC, respectively. Density functional theory calculation reveals OH− has a stronger trend to adsorb on the surface of FeNi‐LDH side in the p‐n junction compared to individual FeNi‐LDH further verifying the synergistic effect in the p‐n junction. Additionally, it represents excellent activity toward water splitting. The utilization of heterojunctions would open up an entirely new possibility to purposefully regulate the electronic structure of active sites and promote their catalytic activities.

Highly Selective Photoreduction of CO2 with Suppressing H2 Evolution over Monolayer Layered Double Hydroxide under Irradiation above 600 nm

By Ling Tan, Si‐Min Xu, Zelin Wang, Yanqi Xu, Xian Wang, Xiaojie Hao, Sha Bai, Chenjun Ning, Yu Wang, Wenkai Zhang, Yun Kyung Jo, Seong‐Ju Hwang, Xingzhong Cao, Xusheng Zheng, Hong Yan, Yufei Zhao, Haohong Duan, Yu‐Fei Song from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

The selectivity of CH4 reached 70.3 % and the by‐product H2 was completely suppressed by monolayer‐NiAl‐LDH in CO2 photoreduction under irradiation with λ>600 nm. The defect state in monolayer‐NiAl‐LDH plays an important role in the outstanding selectivity by localizing the photogenerated electrons excited by photons with λ>600 nm. Abstract Although progress has been made to improve photocatalytic CO2 reduction under visible light (λ>400 nm), the development of photocatalysts that can work under a longer wavelength (λ>600 nm) remains a challenge. Now, a heterogeneous photocatalyst system consisting of a ruthenium complex and a monolayer nickel‐alumina layered double hydroxide (NiAl‐LDH), which act as light‐harvesting and catalytic units for selective photoreduction of CO2 and H2O into CH4 and CO under irradiation with λ>400 nm. By precisely tuning the irradiation wavelength, the selectivity of CH4 can be improved to 70.3 %, and the H2 evolution reaction can be completely suppressed under irradiation with λ>600 nm. The photogenerated electrons matching the energy levels of photosensitizer and m‐NiAl‐LDH only localized at the defect state, providing a driving force of 0.313 eV to overcome the Gibbs free energy barrier of CO2 reduction to CH4 (0.127 eV), rather than that for H2 evolution (0.425 eV).

Breaking Parallel Orientation of Rods via a Dendritic Architecture toward Diverse Supramolecular Structures

By Ruimeng Zhang, Xueyan Feng, Rui Zhang, Wenpeng Shan, Zebin Su, Jialin Mao, Chrys Wesdemiotis, Jiahao Huang, Xiao‐Yun Yan, Tong Liu, Tao Li, Mingjun Huang, Zhiwei Lin, An‐Chang Shi, Stephen Z. D. Cheng from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

The preferred parallel orientation of rod‐like molecules is successfully broken by synergistic effects of hydrogen bonding interaction and dendritic architecture. The resulting molecular shape (fan‐like shape and cone‐like shape) with balanced enthalpy and entropy regulates the formation of diverse supramolecular structures with the curved interface. Abstract Self‐assembled nanostructures of rod‐like molecules are commonly limited to nematic or layered smectic structures dominated by the parallel arrangement of the rod‐like components. Distinct self‐assembly behavior of four categories of dendritic rods constructed by placing a tri(hydroxy) group at the apex of dendritic oligo‐fluorenes is observed. Designed hydrogen bonding and dendritic architecture break the parallel arrangement of the rods, resulting in molecules with specific (fan‐like or cone‐like) shapes. While the fan‐shaped molecules tend to form hexagonal packing cylindrical phases, the cone‐shaped molecules could form spherical motifs to pack into various ordered structures, including the Frank–Kasper A15 phase and dodecagonal quasicrystal. This study provides a model system to engineer diverse supramolecular structures by rod‐like molecules and sheds new light into the mechanisms of the formation of unconventional spherical packing structures in soft matter.

Lock‐and‐Key and Shape‐Memory Effects in an Unconventional Synthetic Path to Magnesium Metal–Organic Frameworks

By Huajun Yang, Thuong Xinh Trieu, Xiang Zhao, Yanxiang Wang, Yong Wang, Pingyun Feng, Xianhui Bu from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

A chilling pore opening: A cold CO2 stream becomes the secret code for opening a tightly sealed and extra‐framework‐cation‐guarded anionic Mg metal–organic framework (MOF). Once open, various gas molecules can freely dance into or swing out of rigidized channels, until being locked out again. Abstract We report a new magnesium metal–organic framework (MOF) (CPM‐107) with a special interaction with CO2. CPM‐107 contains Mg2‐acetate chains crosslinked into a 3D net by terephthalate. It has an anionic framework encapsulating ordered extra‐framework cations and solvent molecules. The desolvated form is closed and unresponsive to common gasses, such as N2, H2, and CH4. Yet, with CO2 at 195 K, it abruptly opens and turns into a rigid porous form that is irreversible via desorption. Once opened by CO2, CPM‐107 remains in the stable porous state accessible to additional gas types over multiple cycles or CO2 itself at different temperatures. The porous phase can be re‐locked to return to the initial closed phase via re‐solvation and desolvation. Such peculiar properties of CPM‐107 are apparently linked to a convergence of factors related to both framework and extra‐framework features. The unusual CO2 effect is currently the only available path to porous CPM‐107 which shows efficient C2H2/CO2 separation.

Expanding APEX2 Substrates for Proximity‐Dependent Labeling of Nucleic Acids and Proteins in Living Cells

By Ying Zhou, Gang Wang, Pengchong Wang, Zeyao Li, Tieqiang Yue, Jianbin Wang, Peng Zou from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Place label here: A panel of biotin‐conjugated aromatic probes were synthesized and screened for APEX2‐mediated proximity labeling of protein, DNA, and RNA. Among these, biotin‐aniline emerged as an efficient probe for capturing the subcellular transcriptome in living cells with high spatial specificity. Abstract The subcellular organization of biomolecules such as proteins and nucleic acids is intimately linked to their biological functions. APEX2, an engineered ascorbate peroxidase that enables proximity‐dependent labeling of proteins in living cells, has emerged as a powerful tool for deciphering the molecular architecture of various subcellular structures. However, only phenolic compounds have thus far been employed as APEX2 substrates, and the resulting phenoxyl radicals preferentially react with electron‐rich amino acid residues. This narrow scope of substrates could potentially limit the application of APEX2. In this study, we screened a panel of aromatic compounds and identified biotin‐conjugated arylamines as novel probes with significantly higher reactivity towards nucleic acids. As a demonstration of the spatial specificity and depth of coverage in mammalian cells, we applied APEX2 labeling with biotin‐aniline (Btn‐An) in the mitochondrial matrix, capturing all 13 mitochondrial messenger RNAs and none of the cytoplasmic RNAs. APEX2‐mediated Btn‐An labeling of RNA is thus a promising method for mapping the subcellular transcriptome, which could shed light on its functions in cell physiology.

Ethynylphosphonamidates for the Rapid and Cysteine‐Selective Generation of Efficacious Antibody–Drug Conjugates

By Marc‐André Kasper, Andreas Stengl, Philipp Ochtrop, Marcus Gerlach, Tina Stoschek, Dominik Schumacher, Jonas Helma, Martin Penkert, Eberhard Krause, Heinrich Leonhardt, Christian P. R. Hackenberger from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

ADphosphonamidateC: Ethynylphosphonamidate conjugation enables straightforward synthesis of ADCs with excellent linkage stability in serum and promising antitumor activity in vivo. The phosphorous core structure of the labeling reagent enables the attachment of an ethylene glycol motif to increase linkage hydrophilicity. Abstract Requirements for novel bioconjugation reactions for the synthesis of antibody–drug conjugates (ADCs) are exceptionally high, since conjugation selectivity as well as the stability and hydrophobicity of linkers and payloads drastically influence the performance and safety profile of the final product. We report Cys‐selective ethynylphosphonamidates as new reagents for the rapid generation of efficacious ADCs from native non‐engineered monoclonal antibodies through a simple one‐pot reduction and alkylation. Ethynylphosphonamidates can be easily substituted with hydrophilic residues, giving rise to electrophilic labeling reagents with tunable solubility properties. We demonstrate that ethynylphosphonamidate‐linked ADCs have excellent properties for next‐generation antibody therapeutics in terms of serum stability and in vivo antitumor activity.

REI5O14 (RE=Y and Gd): Promising SHG Materials Featuring the Semicircle‐Shaped I5O143− Polyiodate Anion

By Jin Chen, Chun‐Li Hu, Fei‐Fei Mao, Bing‐Ping Yang, Xiao‐Han Zhang, Jiang‐Gao Mao from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Going in semicircles: The first examples of rare‐earth polyiodates, namely, REI5O14 (RE=Y and Gd), feature a brand‐new semicircle‐shaped [I5O14]3− pentameric polyiodate anion and exhibit very large second‐harmonic generation signals (14× and 15×KDP). Abstract The first examples of rare‐earth polyiodates, namely, REI5O14 (RE=Y and Gd), have been prepared by hydrothermal reactions of RE2O3 and H5IO6 in H3PO4 (≥85 wt % in H2O), with extremely high yields (>95 %). They crystalize in the polar space group Cm and feature a brand‐new semicircle‐shaped [I5O14]3− pentameric polyiodate anion composed of two IO3 and three IO4 polyhedra. Remarkably, both compounds exhibit very large second‐harmonic generation (SHG) signals (14× and 15×KH2PO4 (KDP) upon 1064 nm laser radiation for Y and Gd compounds, respectively). Our work shows that the hydrothermal reaction in a phosphoric acid medium facilitates the formation of rare‐earth polyiodates.

Dibenzoarsepins: Planarization of 8π‐Electron System in the Lowest Singlet Excited State

By Ikuo Kawashima, Hiroaki Imoto, Masatoshi Ishida, Hiroyuki Furuta, Shunsuke Yamamoto, Masaya Mitsuishi, Susumu Tanaka, Toshiki Fujii, Kensuke Naka from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Aromaticity in the excited state: Dibenzoarsepins possessing formally 8π‐electron systems show highly bent structures in the ground states, while quasi‐planar structures are favored in the singlet excited states. The drastic conformational change upon photoexcitation is in line with Baird's rule. Abstract Dibenzo[b,f]arsepins possessing severely distorted cores compared to those of other heteropins were synthesized. These derivatives exhibited dual photoluminescence in the green‐to‐red region (500–700 nm) and the near‐ultraviolet region (

Ultrafast and Highly Selective Uranium Extraction from Seawater by Hydrogel‐like Spidroin‐based Protein Fiber

By Yihui Yuan, Qiuhan Yu, Jun Wen, Chaoyang Li, Zhanhu Guo, Xiaolin Wang, Ning Wang from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Crazy for U: A chimeric spidroin‐based super uranyl‐binding protein (SSUP) fiber was prepared by biomimetic spinning and used for the efficient extraction of uranium from seawater. The SSUP protein fiber exhibited high, specific, and fast uranium adsorption and showed high reusability. Abstract For the practical extraction of uranium from seawater, adsorbents with high adsorption capacity, fast equilibrium rate, high selectivity, and long service life are needed. Herein, a chimeric spidroin‐based super uranyl‐binding protein (SSUP) fiber was designed by fusing the gene of super uranyl‐binding protein (SUP) with the gene of spidroin. SUP endowed the SSUP fiber with high affinity and selectivity to uranium, and spidroin gave the SSUP fiber with high mechanical strength and high reusability. The wet SSUP fiber is a water‐rich hydrogel‐like structure, which provided abundant hydrophilic intermolecular space for the entrance of uranyl ions, and could accelerate the rate for uranium adsorption. In seawater, the SSUP fiber achieved a breakthrough uranium extraction capacity of 12.33 mg g−1 with an ultrashort equilibration time of 3.5 days, suggesting that SSUP fiber might be a promising adsorbent for uranium extraction from the natural seawater.

Catalytic Ammonia Oxidation to Dinitrogen by Hydrogen Atom Abstraction

By Papri Bhattacharya, Zachariah M. Heiden, Geoffrey M. Chambers, Samantha I. Johnson, R. Morris Bullock, Michael T. Mock from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Totally radical: A molecular Ru complex catalytically oxidizes NH3 to dinitrogen under ambient conditions. The cleavage of six N−H bonds and the formation of an N≡N bond was achieved by coupling H+ and e− transfers as net hydrogen atom abstraction (HAA) steps using the 2,4,6‐tri‐tert‐butylphenoxyl radical (tBu3ArO.) as the H atom acceptor, resulting in up to 10 turnovers. Abstract Catalysts for the oxidation of NH3 are critical for the utilization of NH3 as a large‐scale energy carrier. Molecular catalysts capable of oxidizing NH3 to N2 are rare. This report describes the use of [Cp*Ru(PtBu2NPh2)(15NH3)][BArF4], (PtBu2NPh2=1,5‐di(phenylaza)‐3,7‐di(tert‐butylphospha)cyclooctane; ArF=3,5‐(CF3)2C6H3), to catalytically oxidize NH3 to dinitrogen under ambient conditions. The cleavage of six N−H bonds and the formation of an N≡N bond was achieved by coupling H+ and e− transfers as net hydrogen atom abstraction (HAA) steps using the 2,4,6‐tri‐tert‐butylphenoxyl radical (tBu3ArO.) as the H atom acceptor. Employing an excess of tBu3ArO. under 1 atm of NH3 gas at 23 °C resulted in up to ten turnovers. Nitrogen isotopic (15N) labeling studies provide initial mechanistic information suggesting a monometallic pathway during the N⋅⋅⋅N bond‐forming step in the catalytic cycle.

Paramagnetic Carbon Nanosheets with Random Hole Defects and Oxygenated Functional Groups

By Sun‐Min Jung, Jungmin Park, Dongbin Shin, Hu Young Jeong, DongKyu Lee, In‐Yup Jeon, HyungJoon Cho, Noejung Park, Jung‐Woo Yoo, Jong‐Beom Baek from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Ordered graphitic carbon nanosheets (GCNs) were prepared by the direct dehydration of phenylacetyl units using powerful dehydrating agent, phosphorous pentoxide (P2O5). The GCNs, with random hole defects and remnant oxygenated groups, displayed paramagnetism. The correlation between structure and magnetism was manifested by experiments and calculations. Abstract Ordered graphitic carbon nanosheets (GCNs) were, for the first time, synthesized by the direct condensation of multifunctional phenylacetyl building blocks (monomers) in the presence of phosphorous pentoxide. The GCNs had highly ordered structures with random hole defects and oxygenated functional groups, showing paramagnetism. The results of combined structural and magnetic analyses indicate that the hole defects and functional groups are associated with the appearance and stabilization of unpaired spins. DFT calculations further suggest that the emergence of stabilized spin moments near the edge groups necessitates the presence of functionalized carbon atoms around the hole defects. That is, both hole defects and oxygenated functional groups are essential ingredients for the generation and stabilization of spins in GCNs.

Metal–Organic Framework‐Activated Carbon Composite Materials for the Removal of Ammonia from Contaminated Airstreams

By Lauren N. McHugh, Angela Terracina, Paul S. Wheatley, Gianpiero Buscarino, Martin W. Smith, Russell E. Morris from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Crystals in coal: A new series of MOF‐activated carbon composite materials are synthesised, using the copper MOF: STAM‐17‐OEt and commercially available BPL activated carbon. STAM‐17‐OEt is grown inside BPL carbon at three loadings to provide a series of granular materials that display excellent gas adsorption properties and water stability. Abstract Metal–organic frameworks (MOFs) are a class of porous materials that show promise in the removal of toxic industrial chemicals (TICs) from contaminated airstreams, though their development for this application has so far been hindered by issues of water stability and the wide availability and low cost of traditionally used activated carbons. Here a series of three MOF‐activated carbon composite materials with different MOF to carbon ratios are prepared by growing STAM‐17‐OEt crystals inside the commercially available BPL activated carbon. The composite materials display excellent water stability and increased uptake of ammonia gas when compared to unimpregnated carbon. Such properties make these composites very promising in the fields of air purification and personal protective equipment.

A Switchable Domino Process for the Construction of Novel CO2‐Sourced Sulfur‐Containing Building Blocks and Polymers

By Farid Ouhib, Bruno Grignard, Elias Van Den Broeck, André Luxen, Koen Robeyns, Veronique Van Speybroeck, Christine Jerome, Christophe Detrembleur from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

High atom economy: Linear thiocarbonates and elusive tetrasubstituted ethylene carbonates are accessible in high yields from the organocatalyzed chemoselective addition of thiols to α‐alkylidene cyclic carbonates thanks to a switchable domino process. This robust synthetic method is also exploited for the facile construction of a large diversity of unprecedented sulfur‐containing polymers. Abstract α‐Alkylidene cyclic carbonates (αCCs) recently emerged as attractive CO2‐sourced synthons for the construction of complex organic molecules. Herein, we report the transformation of αCCs into novel families of sulfur‐containing compounds by organocatalyzed chemoselective addition of thiols, following a domino process that is switched on/off depending on the desired product. The process is extremely fast and versatile in substrate scope, provides selectively linear thiocarbonates or elusive tetrasubstituted ethylene carbonates with high yields following a 100 % atom economy reaction, and valorizes CO2 as a renewable feedstock. It is also exploited to produce a large diversity of unprecedented functional polymers. It constitutes a robust platform for the design of new sulfur‐containing organic synthons and important families of polymers.

[Am(C5Me4H)3]: An Organometallic Americium Complex

By Conrad A. P. Goodwin, Jing Su, Thomas E. Albrecht‐Schmitt, Anastasia V. Blake, Enrique R. Batista, Scott R. Daly, Stefanie Dehnen, William J. Evans, Andrew J. Gaunt, Stosh A. Kozimor, Niels Lichtenberger, Brian L. Scott, Ping Yang from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Captain americium: The first structural characterization of an Am−C molecular interaction along with a suite of standard synthetic chemistry characterization techniques, including both 1H NMR and solution UV/Vis‐NIR spectroscopy have been performed. Detailed theoretical models of the electronic structure show excellent agreement with experimental data. Abstract We report the small‐scale synthesis, isolated yield, single‐crystal X‐ray structure, 1H NMR solution spectroscopy /solid‐state UV/Vis‐nIR spectroscopy, and density functional theory (DFT)/ab initio wave function theory calculations on an Am3+ organometallic complex, [Am(C5Me4H)3] (1). This constitutes the first quantitative data on Am−C bonding in a molecular species.

Regioselective Formal [3+2] Cycloadditions of Urea Substrates with Activated and Unactivated Olefins for Intermolecular Olefin Aminooxygenation

By Fan Wu, Nur‐E Alom, Jeewani P. Ariyarathna, Johannes Naß, Wei Li from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Full circle: An iodide‐catalyzed olefin aminooxygenation reaction is described. This reaction enables the direct coupling of urea substrates with both activated and unactivated alkenes to afford a range of interesting heterocyclic structures with a high degree of regio‐ and stereochemical control. Abstract A new class of intermolecular olefin aminooxygenation reaction is described. This reaction utilizes the classic halonium intermediate as a regio‐ and stereochemical template to accomplish the selective oxyamination of both activated and unactivated alkenes. Notably, urea chemical feedstock can be directly introduced as the N and O source and a simple iodide salt can be utilized as the catalyst. This formal [3+2] cycloaddition process provides a highly modular entry to a range of useful heterocyclic products with excellent selectivity and functional‐group tolerance.

Synthesis of Functionalized Medium‐Sized trans‐Cycloalkenes by 4π Electrocyclic Ring Opening/Alkylation Sequence

By Tomohiro Ito, Masaki Tsutsumi, Ken‐ichi Yamada, Hiroshi Takikawa, Yousuke Yamaoka, Kiyosei Takasu from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Ts & Cs: Preparation of medium‐sized trans‐cycloalkenes (TCAs) bearing functional groups are accomplished by a domino 4π electrocyclic ring opening/alkylation sequence, via short‐lived cis,trans‐siloxycycloalkadiene intermediates, in a stereocontrolled manner. The preparation of optically pure trans‐cyclooctenes by a chirality transfer strategy was also demonstrated. Abstract Development of a novel synthetic method for medium‐sized trans‐cycloalkenes (TCAs) is described. Functionalized TCAs are readily prepared from simple cycloalkanones in a few steps, namely, enol silyl ether formation, [2+2] cycloaddition, and domino 4π electrocyclic ring opening/alkylation (conjugate addition). The first example of central‐to‐planar chirality transfer from enantiomerically enriched cyclobutenes to TCAs is also described.

Chemoenzymatic Platform for Synthesis of Chiral Organofluorines Based on Type II Aldolases

By Jason Fang, Diptarka Hait, Martin Head‐Gordon, Michelle C. Y. Chang from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Pyruvate aldolases of the type II HpcH family are excellent catalysts for fluoropyruvate addition to aldehydes. The stereoselectivity and kinetic behavior are rationalized, and engineering of hydroxyl stereoselectivity is demonstrated. Downstream reactions allow the synthesis of numerous fluorinated analogs of sugars, amino acids, and other valuable chiral organofluorines. Abstract Aldolases are C−C bond forming enzymes that have become prominent tools for sustainable synthesis of complex synthons. However, enzymatic methods of fluorine incorporation into such compounds are lacking due to the rarity of fluorine in nature. Recently, the use of fluoropyruvate as a non‐native aldolase substrate has arisen as a solution. Here, we report that the type II HpcH aldolases efficiently catalyze fluoropyruvate addition to diverse aldehydes, with exclusive (3S)‐selectivity at fluorine that is rationalized by DFT calculations on a mechanistic model. We also measure the kinetic parameters of aldol addition and demonstrate engineering of the hydroxyl group stereoselectivity. Our aldolase collection is then employed in the chemoenzymatic synthesis of novel fluoroacids and ester derivatives in high stereopurity (d.r. 80–98 %). The compounds made available by this method serve as precursors to fluorinated analogs of sugars, amino acids, and other valuable chiral building blocks.

Revealing the Distribution of Metal Carboxylates in Oil Paint from the Micro‐ to Nanoscale

By Xiao Ma, Victoria Beltran, Georg Ramer, Georges Pavlidis, Dilworth Y. Parkinson, Mathieu Thoury, Tyler Meldrum, Andrea Centrone, Barbara H. Berrie from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

IR nanoscopy of paints: A new implementation of a compositionally sensitive AFM‐based method (PTIR) reveals metal‐soaps (metal carboxylate) composition and heterogeneous distribution in naturally aged paints. Abstract Oil paints comprise pigments, drying oils, and additives that together confer desirable properties, but can react to form metal carboxylates (soaps) that may damage artworks over time. To obtain information on soap formation and aggregation, we introduce a new tapping‐mode measurement paradigm for the photothermal induced resonance (PTIR) technique that enables nanoscale IR spectroscopy and imaging on highly heterogenous and rough paint thin sections. PTIR is used in combination with μ‐computed tomography and IR microscopy to determine the distribution of metal carboxylates in a 23‐year old oil paint of known formulation. Results show that heterogeneous agglomerates of Al‐stearate and a Zn‐carboxylate complex with Zn‐stearate nano‐aggregates in proximity are distributed randomly in the paint. The gradients of zinc carboxylates are unrelated to the Al‐stearate distribution. These measurements open a new chemically sensitive nanoscale observation window on the distribution of metal soaps that can bring insights for understanding soap formation in oil paint.

Phase Regulation Strategy of Perovskite Nanocrystals from 1D Orthomorphic NH4PbI3 to 3D Cubic (NH4)0.5Cs0.5Pb(I0.5Br0.5)3 Phase Enhances Photoluminescence

By Chao Wang, Yue Liu, Xia Feng, Chenyang Zhou, Yalan Liu, Xi Yu, Guangjiu Zhao from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

More than just a phase: NH4PbI3 and (NH4)0.5Cs0.5Pb(I0.5Br0.5)3 perovskite nanocrystals are both synthesized for the first time by a phase regulation strategy. (NH4)0.5Cs0.5Pb(I0.5Br0.5)3 perovskite nanocrystals exhibit markedly enhanced photoluminescence and better stability. Abstract This work reports this first synthesis of 1D orthomorphic NH4PbI3 perovskite nanocrystals (NCs) considering the role of inorganic ammonium ions at the nanoscale. The addition of bromide ions at the halogen site did not improve the photoluminescence properties. Furthermore, the 3D cubic phase of (NH4)0.5Cs0.5Pb(I0.5Br0.5)3 NCs with bright photoluminescence was synthesized by adding Cs ions into the crystal lattice of (NH4)Pb(I0.5Br0.5)3. Moreover, the photophysical properties of different phase structures were studied using femtosecond transient absorption (FTA) spectroscopy. The ultrafast trap state capture process is a key factor in the change of photoluminescence properties and the cubic phase may be the best structure for photoluminescence. These results suggest that the ammonium ion perovskite (AIP) nanocrystals could be potential materials for optoelectronic applications through A‐site cation substitution.

In vitro Reconstitution of the Biosynthetic Pathway to the Nitroimidazole Antibiotic Azomycin

By Jason B. Hedges, Katherine S. Ryan from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Nitroimidazole antibiotics are widely used to treat anaerobic bacterial infections. The first nitroimidazole azomycin was isolated from bacteria over 60 years ago, but the enzymes involved in azomycin production were not identified. The in vitro reconstitution of the elusive azomycin biosynthetic enzymes, which are in a widely distributed core biosynthetic gene cluster, is now possible. Abstract Nitroimidazoles are one of the most effective ways to treat anaerobic bacterial infections. Synthetic nitroimidazoles are inspired by the structure of azomycin, isolated from Streptomyces eurocidicus in 1953. Despite its foundational role, no biosynthetic gene cluster for azomycin has been found. Guided by bioinformatics, we identified a cryptic biosynthetic gene cluster in Streptomyces cattleya and then carried out in vitro reconstitution to deduce the enzymatic steps in the pathway linking l‐arginine to azomycin. The gene cluster we discovered is widely distributed among soil‐dwelling actinobacteria and proteobacteria, suggesting that azomycin and related nitroimidazoles may play important ecological roles. Our work sets the stage for development of biocatalytic approaches to generate azomycin and related nitroimidazoles.

Tunable Surface Area, Porosity, and Function in Conjugated Microporous Polymers

By Jie Chen, Wei Yan, Esther J. Townsend, Jiangtao Feng, Long Pan, Veronica Del Angel Hernandez, Charl F. J. Faul from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Porous, with a pinch of salt: The discovery of the BXJ approach, where salts are used to carefully tune N‐containing conjugated microporous materials, is reported. This approach enables the preparation of amorphous porous materials that start to challenge COFs and MOFs in properties and function. Abstract Simple inorganic salts are used to tune N‐containing conjugated microporous polymers (CMPs) synthesized by Buchwald–Hartwig (BH) cross‐coupling reactions. Poly(triphenylamine), PTPA, initially shows a broad distribution of micropores, mesopores, and macropores. However, the addition of inorganic salts affects all porous network properties significantly: the pore size distribution is narrowed to the microporous range only, mimicking COFs and MOFs; the BET surface area is radically improved from 58 m2 g−1 to 1152 m2 g−1; and variations of the anion and cation sizes are used to fine‐tune the surface area of PTPA, with the surface area showing a gradual decrease with an increase in the ionic radius of salts. The effect of the salt on the physical properties of the polymer is attributed to adjusting and optimizing the Hansen solubility parameters (HSPs) of solvents for the growing polymer, and named the Beijing–Xi'an Jiaotong (BXJ) method.

1,2‐(Bis)trifluoromethylation of Alkynes: A One‐Step Reaction to Install an Underutilized Functional Group

By Shuo Guo, Deyaa I. AbuSalim, Silas P. Cook from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Two of a kind: A copper‐mediated 1,2‐(bis)trifluoromethylation of acetylenes enables the preparation of E‐hexafluorobutenes (E‐HFBs) in a single step. The reaction proceeds with high yield and E/Z selectivity under blue light. Mechanistic work elucidates the frontier molecular orbital behavior of the copper complex and the role of persulfate. Abstract Modifying the electronic properties of olefins is the quintessential approach to tuning alkene reactivity. In this context, the exploration of trifluoromethyl groups as divergent electronic modifiers has not been considered. In this work, we describe a copper‐mediated 1,2‐(bis)trifluoromethylation of acetylenes to create E‐hexafluorobutenes (E‐HFBs) under blue light in a single step. The reaction proceeds with high yield and E/Z selectivity. Since the alkyne captures two trifluoromethyl groups from each molecule of bpyCu(CF3)3, mechanistic studies were conducted to illuminate the role of the reactants. Interestingly, E‐HFBs exhibit remarkable stability to standard olefin functionalization reactions in spite of the pendant trifluoromethyl groups. This finding has significant implications for medicine, agroscience, and materials.

Prediction of Fluorooxoborates with Colossal Second Harmonic Generation (SHG) Coefficients and Extremely Wide Band Gaps: Towards Modulating Properties by Tuning the BO3/BO3F Ratio in Layers

By Bingbing Zhang, Evgenii Tikhonov, Congwei Xie, Zhihua Yang, Shilie Pan from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Fluorooxoborates have inspired investigations of deep‐ultraviolet (DUV) nonlinear optical (NLO) materials. Five stable structures with the composition of BaB2O3F2 (I–V) are discovered using the ab initio evolutionary algorithm. Among them, BaB2O3F2‐I is known and confirms the reliability of the method. It shows that BO3F groups can give large band gaps and strong second harmonic generation (SHG) responses. Abstract Fluorooxoborates have inspired investigations of deep‐ultraviolet (DUV) nonlinear optical (NLO) materials that can meet the multiple criteria. Herein, five stable structures with the composition of BaB2O3F2 (I–V) are discovered using the ab initio evolutionary algorithm. Among them, BaB2O3F2‐I has been synthesized experimentally and confirms the reliability of the method. All of the predicted structures possess extremely wide band gaps (8.1–9.0 eV). Moreover, four new structures exhibit giant second harmonic generation (SHG) coefficients (>3×KDP, d36=0.39 pm V−1). A novel type of the [BOF] layer with BO3:BO3F ratio of [1:1] is found in BaB2O3F2‐II and BaB2O3F2‐III. While BaB2O3F2‐IV and BaB2O3F2‐V are solely composed of the BO3F group and have colossal SHG coefficients (ca. 4×KDP). It gives the direct evidence that the BO3F group could generate strong SHG effect. Most importantly, the influences of BO3:BO3F ratio and their number density on band gap, birefringence and SHG effects are investigated.

Isolated Square‐Planar Copper Center in Boron Imidazolate Nanocages for Photocatalytic Reduction of CO2 to CO

By Hai‐Xia Zhang, Qin‐Long Hong, Jing Li, Fei Wang, Xinsong Huang, Shumei Chen, Wenguang Tu, Dingshan Yu, Rong Xu, Tianhua Zhou, Jian Zhang from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

The cat on the cage: A copper‐based boron imidazolate cage with isolated, coordinatively unsaturated single copper atom active sites was found to be as an excellent co‐catalyst for highly efficient and selective solar‐driven CO2 reduction to CO. Abstract Photocatalytic reduction of CO2 to value‐added fuel has been considered to be a promising strategy to reduce global warming and shortage of energy. Rational design and synthesis of catalysts to maximumly expose the active sites is the key to activate CO2 molecules and determine the reaction selectivity. Herein, we synthesize a well‐defined copper‐based boron imidazolate cage (BIF‐29) with six exposed mononuclear copper centers for the photocatalytic reduction of CO2. Theoretical calculations show a single Cu site including weak coordinated water delivers a new state in the conduction band near the Fermi level and stabilizes the *COOH intermediate. Steady‐state and time‐resolved fluorescence spectra show these Cu sites promote the separation of electron–hole pairs and electron transfer. As a result, the cage achieves solar‐driven reduction of CO2 to CO with an evolution rate of 3334 μmol g−1 h−1 and a high selectivity of 82.6 %.

Pre‐oxidation of Gold Nanoclusters Results in a 66 % Anodic Electrochemiluminescence Yield and Drives Mechanistic Insights

By Huaping Peng, Zhongnan Huang, Yilun Sheng, Xiangping Zhang, Haohua Deng, Wei Chen, Juewen Liu from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Gold gets glowing: An efficient method for the accurate regulation of the anodic electrochemiluminescence (ECL) of gold nanoclusters (AuNCs) was achieved by pre‐oxidation of the AuNCs. A record high ECL yield of 66 % was achieved, which established a mechanistic framework for fundamental understanding and future improvements. Abstract Gold nanoclusters (AuNCs) are attractive electrochemiluminescence (ECL) emitters because of their excellent stability, near IR emission, and biocompatibility. However, their ECL quantum yield is relatively low, and our limited fundamental understanding has hindered rational improvement of this parameter. Herein, we report drastic enhancement of the ECL of ligand‐stabilized AuNCs by on‐electrode pre‐oxidation with triethylamine (TEA) as a co‐reactant. The l‐methionine‐stabilized AuNCs resulted in a record high ECL yield of 66 %. This strategy was successfully extended to other AuNCs, and it is more effective for ligand shells that allow more effective electron transfer. In addition, excitation of the pre‐oxidized ECL required a lower potential than conventional methods, and no additional instrument was required. This work opens avenues for solving a challenging problem of AuNC‐based ECL probes and enriches fundamental understanding, greatly broadening their potential applications.

In‐situ Chemiluminescence‐Driven Reversible Addition–Fragmentation Chain‐Transfer Photopolymerization

By Nethmi De Alwis Watuthanthrige, Michael L. Allegrezza, Madison T. Dolan, Alex J. Kloster, Marina Kovaliov, Saadyah Averick, Dominik Konkolewicz from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Lights on and initiate: Chemiluminescence is used to drive polymerization reactions. A biphasic reaction is developed such that light‐generating reactions are confined to the organic phase and photopolymerization occurs in the aqueous phase. Well‐defined RAFT‐capped polymers are synthesized and the kinetics are shown to be dictated by light generation. Abstract The power of chemical light generation (chemiluminescence) is used to drive polymerization reactions. A biphasic reaction is developed such that light‐generating reactions are confined to the organic phase and photopolymerization occurs in the aqueous phase. Well‐defined RAFT‐capped polymers are synthesized and the kinetics are shown to be dictated by light generation.

Negative Charging of Transition‐Metal Phosphides via Strong Electronic Coupling for Destabilization of Alkaline Water

By Bo You, Yadong Zhang, Yan Jiao, Kenneth Davey, Shi Zhang Qiao from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Negative charging of various transition‐metal phosphides by strong electronic coupling with corresponding hydr(oxy)oxides formed in situ accelerates destabilization of alkaline water for boosted H2 evolution. Abstract Heterogeneous electrocatalysis typically involves charge transfer between surface active sites and adsorbed species. Therefore, modulating the surface charge state of an electrocatalyst can be used to enhance performance. A series of negatively charged transition‐metal (Fe, Co, Ni, Cu,and NiCo) phosphides were fabricated by designing strong electronic coupling with hydr(oxy)oxides formed in situ. Physicochemical characterizations, together with DFT computations, demonstrate that strong electronic coupling renders transition‐metal phosphides negatively charged. This facilitates destabilization of alkaline water adsorption and dissociation to result in significantly improved H2 evolution. Negatively charged Ni2P/nickel hydr(oxy)oxide for example exhibits a significantly low overpotential of 138 mV at 100 mA cm−2, superior to that without strong electronic coupling and also commercial Pt/C.

Enhanced Charge Transport by Incorporating Formamidinium and Cesium Cations into Two‐Dimensional Perovskite Solar Cells

By Liguo Gao, Fei Zhang, Xihan Chen, Chuanxiao Xiao, Bryon W. Larson, Sean P. Dunfield, Joseph J. Berry, Kai Zhu from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Triple whammy: Reported here is the fabrication of 2D perovskites (n=5) with triple cations. The resulting perovskites feature longer carrier lifetime, greater mobility, and higher conductivity. The efficiency of 2D perovskite solar cells (PSCs) with triple cations was enhanced by more than 80 % (from 7.80 to 14.23 %) compared to PSCs fabricated with a monocation. The efficiency is also higher than that of PSCs based on binary cation 2D structures. Abstract Organic‐inorganic hybrid two‐dimensional (2D) perovskites (n≤5) have recently attracted significant attention because of their promising stability and optoelectronic properties. Normally, 2D perovskites contain a monocation [e.g., methylammonium (MA+) or formamidinium (FA+)]. Reported here for the first time is the fabrication of 2D perovskites (n=5) with mixed cations of MA+, FA+, and cesium (Cs+). The use of these triple cations leads to the formation of a smooth, compact surface morphology with larger grain size and fewer grain boundaries compared to the conventional MA‐based counterpart. The resulting perovskite also exhibits longer carrier lifetime and higher conductivity in triple cation 2D perovskite solar cells (PSCs). The power conversion efficiency (PCE) of 2D PSCs with triple cations was enhanced by more than 80 % (from 7.80 to 14.23 %) compared to PSCs fabricated with a monocation. The PCE is also higher than that of PSCs based on binary cation (MA+‐FA+ or MA+‐Cs+) 2D structures.

Cyclobis(7,8‐(para‐quinodimethane)‐4,4′‐triphenylamine) and Its Cationic Species Showing Annulene‐Like Global (Anti)Aromaticity

By Shaoqiang Dong, Tullimilli Y. Gopalakrishna, Yi Han, Chunyan Chi from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

It's dynamic: The π‐conjugated macrocycle CBQT, containing alternating para‐quinodimethane and triphenylamine units, shows a temperature‐dependent dynamic process. It displays [32]annulene‐like antiaromaticity at low temperatures. Its dication and tetracation exhibit global aromaticity and anti‐aromaticity, respectively. Abstract π‐Conjugated macrocycles containing all‐benzenoid rings usually show local aromaticity, but reported herein is the macrocycle CBQT, containing alternating para‐quinodimethane and triphenylamine units displaying annulene‐like anti‐aromaticity at low temperatures as a result of structural rigidity and participation of the bridging nitrogen atoms in π‐conjugation. It was easily synthesized by intermolecular Friedel–Crafts alkylation followed by oxidative dehydrogenation. X‐ray crystallographic structures of CBQT, as well as those of its dication, trication, and tetracation were obtained. The dication and tetracation exhibited global aromaticity and antiaromaticity, respectively, as confirmed by NMR measurements and theoretical calculations. Both the dication and tetracation possess open‐shell singlet ground states, with a small singlet–triplet gap.

Reactivity of a Tetra(o‐tolyl)diborane(4) Dianion as a Diarylboryl Anion Equivalent

By Seiji Akiyama, Kaito Yamada, Makoto Yamashita from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Two for one: The lithium and magnesium salts of tetra(o‐tolyl)diborane(4) dianion, with B−B double‐bond character, were synthesized. The lithium salt of the dianion reacted as two equivalents of a diarylboryl anion with CH2Cl2 or S8 to give substituted products. Abstract Lithium and magnesium salts of tetra(o‐tolyl)diborane(4) dianion, having B=B double bond character, were synthesized. It was clarified that the lithium salt of the dianion has a high‐lying HOMO and a narrow HOMO–LUMO gap, which were perturbed by dissociation of Li+ cation, as judged by UV/Vis spectroscopy and DFT calculations. The lithium salt of the dianion reacted as two equivalents of a diarylboryl anion with CH2Cl2 or S8 to give boryl‐substituted products.

Development of Chemo‐ and Enantioselective Palladium‐Catalyzed Decarboxylative Asymmetric Allylic Alkylation of α‐Nitroesters

By Barry M. Trost, Johnathan E. Schultz, Yu Bai from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

The development of a Pd‐catalyzed decarboxylative asymmetric allylic alkylation of α‐nitro allyl esters to afford acyclic tetrasubstituted nitroalkanes is described. Optimization of the reaction parameters revealed unique ligand and solvent combinations crucial for achieving chemo‐ and enantioselective C‐alkylation of electronically challenging benzylic nitronates and sterically encumbered 2‐allyl esters. Abstract We describe the development of a Pd‐catalyzed decarboxylative asymmetric allylic alkylation of α‐nitro allyl esters to afford acyclic tetrasubstituted nitroalkanes. Optimization of the reaction parameters revealed unique ligand and solvent combinations crucial for achieving chemo‐ and enantioselective C‐alkylation of electronically challenging benzylic nitronates and sterically encumbered 2‐allyl esters. Substrates were efficiently accessed in a combinatorial fashion by a cross‐Claisen/ α‐arylation sequence. The method provides functional group orthogonality that complements nucleophilic imine allylation strategies for α‐tertiary amine synthesis.

Asymmetric Chemoenzymatic Synthesis of (−)‐Podophyllotoxin and Related Aryltetralin Lignans

By Jian Li, Xiao Zhang, Hans Renata from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

(−)‐Podophyllotoxin, a potent microtubule depolymerizing agent, was synthesized in a concise manner through strategic use of three oxidative processes. Highlights of the route include a gram‐scale biocatalytic C−C coupling to construct the tetracyclic core of the natural product and a chemoselective late‐stage installation of the secondary alcohol at C7. Abstract (−)‐Podophyllotoxin is one of the most potent microtubule depolymerizing agents and has served as an important lead compound in antineoplastic drug discovery. Reported here is a short chemoenzymatic total synthesis of (−)‐podophyllotoxin and related aryltetralin lignans. Vital to this approach is the use of an enzymatic oxidative C−C coupling reaction to construct the tetracyclic core of the natural product in a diastereoselective fashion. This strategy allows gram‐scale access to (−)‐deoxypodophyllotoxin and is readily adaptable to the preparation of related aryltetralin lignans.

Hyperaging Tuning of a Carbon Molecular‐Sieve Hollow Fiber Membrane with Extraordinary Gas‐Separation Performance and Stability

By Wulin Qiu, Justin Vaughn, Gongping Liu, Liren Xu, Mark Brayden, Marcos Martinez, Thomas Fitzgibbons, Graham Wenz, William J. Koros from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Better with age: So‐called hyperaging of carbon molecular‐sieve hollow fiber membranes at moderate elevated temperatures leads to a high separation performance for separating hydrogen and hydrocarbons. The system is stable over a long time and therefore very attractive for practical applications. This work provides an opportunity for tuning CMS fiber for the separation of small molecules from large molecules. Abstract This study reports 6FDA:BPDA‐DAM polyimide‐derived hollow fiber carbon molecular‐sieve (CMS) membranes for hydrogen and ethylene separation. Since H2/C2H4 selectivity is the lowest among H2/(C1‐C3) hydrocarbons, an optimized CMS fiber for this gas pair is useful for removing hydrogen from all‐cracked gas mixtures. A process we term hyperaging provides highly selective CMS fiber membranes by tuning CMS ultramicropores to favor H2 over larger molecules to give a H2/C2H4 selectivity of over 250. Hyperaging conditions and a hyperaging mechanism are discussed in terms of an expedited physical aging process, which is largely controlled by the hyperaging temperature. For the specific CMS material considered here, a hyperaging temperature beyond 90 °C but less than 250 °C works best. Hyperaging also stabilizes CMS materials against physical aging and stabilizes the performance of H2 separation over extended periods. This work opens a door in the development of CMS materials for the separation of small molecules from large molecules.

Direct Z‐Scheme Hetero‐phase Junction of Black/Red Phosphorus for Photocatalytic Water Splitting

By Fulai Liu, Rui Shi, Zhuan Wang, Yuxiang Weng, Chi‐Ming Che, Yong Chen from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

The red and the black: A direct Z‐scheme hetero‐phase junction of black phosphorus/red phosphorus (BP/RP) photocatalyst is prepared by a wet‐chemistry method. As a result of their appropriate band structures with a staggered alignment and perfect phase junction interface, the BP/RP hetero‐phase junctions give efficient separation of photogenerated carriers and achieve Z‐scheme photocatalytic water splitting without using sacrificial agents. Abstract Black phosphorus (BP) has recently drawn attention in photocatalysis for its optical properties. However, limited by the rapid recombination of photogenerated carriers, the use of BP for photocatalytic water splitting still remains a huge challenge. Herein, we prepare a black/red phosphorus (BP/RP) hetero‐phase junction photocatalyst by a wet‐chemistry method to promote the interfacial charge separation and thus achieve Z‐scheme photocatalytic water splitting without using sacrificial agents. The Z‐scheme mechanism was confirmed by time‐resolved transient absorption spectroscopy. This work provides a novel insight into the interface design of hetero‐phase junction with atomic precision.

Molecular Engineering‐Based Aptamer–Drug Conjugates with Accurate Tunability of Drug Ratios for Drug Combination Targeted Cancer Therapy

By Fang Zhou, Peng Wang, Yongbo Peng, Pengge Zhang, Qin Huang, Weidi Sun, Nongyue He, Ting Fu, Zilong Zhao, Xiaohong Fang, Weihong Tan from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Ratio(nal) delivery: Circular bivalent aptamer–drug conjugates (cb‐ApDCs) for drug combination cancer therapy have been developed. The cb‐ApDCs offer high stability, specific recognition, excellent cellular uptake, esterase‐triggered release, and tunable the drug ratios for an enhanced synergistic effect. Abstract Polytherapy (or drug combination cancer therapy (DCCT)), targeting multiple mechanisms associated with tumor proliferation, can efficiently maximize therapeutic efficacy, decrease drug dosage, and reduce drug resistance. However, most DCCT strategies cannot coordinate the specific delivery of a drug combination in an accurately tuned ratio into cancer cells. To address these limitations, the present work reports the engineering of circular bivalent aptamer–drug conjugates (cb‐ApDCs). The cb‐ApDCs exhibit high stability, specific recognition, excellent cellular uptake, and esterase‐triggered release. Furthermore, the drug ratios in cb‐ApDCs can be tuned for an enhanced synergistic effect without the need for complex chemistry. Therefore, cb‐ApDCs provide a promising platform for the development of DCCT strategies for different drug combinations and ratios.

Co‐Assembled Supramolecular Nanostructure of Platinum(II) Complex through Helical Ribbon to Helical Tubes with Helical Inversion

By Ka Young Kim, Jaehyeong Kim, Cheol Joo Moon, Jinying Liu, Shim Sung Lee, Myong Yong Choi, Chuanliang Feng, Jong Hwa Jung from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Tubular ribbons: A morphology transformation using metal–metal interactions is exploited in co‐assembled supramolecular nanostructures based on platinum(II) complexes. This approach allows the morphology of the transformation of helical ribbons into tubular structures through helicity inversion to be controlled. Abstract We demonstrated the morphology transformation of co‐assemblies based on terpyridine‐based ligands (1R and 1S) possessing R‐ or S‐alanine analogues and their platinum(II) complex (2R‐Pt and 2S‐Pt). The right‐handed helical ribbon of the co‐assembly formed with 0.5 equivalents of 2R‐Pt to 1R was converted into the left‐handed helical ribbon with 0.6 equivalents of 2R‐Pt. The left‐handed helical ribbon structure of the co‐assembly became a tubular structure in the presence of 0.8–1.0 equivalents of 2R‐Pt. The morphology transformation via helical inversion at the supramolecular level was due to an orientation change of the amide groups caused by non‐covalent Pt⋅⋅⋅Pt interactions between the terpyridine of 2R‐Pt and that of 2R‐Pt. This study provides insights into controlling the morphology of the transformation of helical ribbons into tubular structures through helicity inversion in co‐assembled supramolecular nanostructures based on platinum(II) complexes.

The First Study on the Reactivity of Water Vapor in Metal–Organic Frameworks with Platinum Nanocrystals

By Naoki Ogiwara, Hirokazu Kobayashi, Patricia Concepción, Fernando Rey, Hiroshi Kitagawa from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

On the water front: The reactivity of H2O vapor in metal–organic frameworks (MOFs) with Pt nanocrystals either on the MOF or coated by the MOF is studied by means of the water–gas shift reaction. A water‐stable MOF, UiO‐66, serves as a highly effective support material for the reaction. The origin of the high catalytic performance was investigated using in situ IR spectroscopy. Abstract We first studied the reactivity of H2O vapor in metal–organic frameworks (MOFs) with Pt nanocrystals (NCs) through the water–gas shift (WGS) reaction. A water‐stable MOF, UiO‐66, serves as a highly effective support material for the WGS reaction compared with ZrO2. The origin of the high catalytic performance was investigated using in situ IR spectroscopy. In addition, from a comparison of the catalytic activities of Pt on UiO‐66, where Pt NCs are located on the surface of UiO‐66 and Pt@UiO‐66, where Pt NCs are coated with UiO‐66, we found that the competitive effects of H2O condensation and diffusion in the UiO‐66 play important roles in the catalytic activity of Pt NCs. A thinner UiO‐66 coating further enhanced the WGS reaction activity of Pt NCs by minimizing the negative effect of slow H2O diffusion in UiO‐66.

Atomic‐Scale Insights into Surface Lattice Oxygen Activation at the Spinel/Perovskite interface of Co3O4/La0.3Sr0.7CoO3

By Xiyang Wang, Ziye Pan, Xuefeng Chu, Keke Huang, Yingge Cong, Rui Cao, Ritimukta Sarangi, Liping Li, Guangshe Li, Shouhua Feng from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Activation of surface lattice oxygen: A Co3O4/La0.3Sr0.7CoO3 interface engineered in situ triggers more electrons in the oxygen site of perovskite LSC to be transferred into the lattice of Co3O4. More inactive O2− species are thus transformed into active O2−x species, which efficiently lowers the activation‐energy barriers in surface anion oxygen reactions. Abstract Surface lattice oxygen in transition‐metal oxides plays a vital role in catalytic processes. Mastering activation of surface lattice oxygen and identifying the activation mechanism are crucial for the development and design of advanced catalysts. A strategy is now developed to create a spinel Co3O4 /perovskite La0.3Sr0.7CoO3 interface by in situ reconstruction of the surface Sr enrichment region in perovskite LSC to activate surface lattice oxygen. XAS and XPS confirm that the regulated chemical interface optimizes the hybridized orbital between Co 3d and O 2p and triggers more electrons in oxygen site of LSC transferred into lattice of Co3O4 , leading to more inactive O2− transformed into active O2−x. Furthermore, the activated Co3O4/LSC exhibits the best catalytic activities for CO oxidation, oxygen evolution, and oxygen reduction. This work would provide a fundamental understanding to explain the activation mechanism of surface oxygen sites.

Highly Diastereoselective Synthesis of Syn‐1,3‐Dihydroxyketone Motifs from Propargylic Alcohols via Spiroepoxide Intermediates

By Xiao‐Bo Ding, Daniel P. Furkert, Margaret A. Brimble from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Silver bullet: Highly diastereoselective access to syn dihydroxyketones with broad substrate scope is reported. Silver‐mediated cyclisation of propargylic alcohols with triketone incorporation gives stable enol dioxolanes that are diastereoselectively epoxidised to give unusual spiroepoxide species. Syn dihydroxyketones or their monoacetates are delivered by hydrolysis or acetolysis, respectively. A one‐pot process is also effective. Abstract Syn dihydroxyketone motifs are embedded in a wide range of biologically active natural products, however the development of stereoselective synthetic methods to assemble these structures has proven a challenging task. We report a highly diastereoselective method for the synthesis of syn dihydroxyketones from propargylic alcohols, with wide scope for application in natural product synthesis. The reaction sequence involves regioselective cyclisation of propargylic alcohols with incorporation of a triketone to give enol dioxolanes that are then diastereoselectively epoxidised to form unusual spiroepoxide intermediates. Hydrolysis affords syn dihydroxyketones as essentially single diastereisomers. The reaction sequence is operationally simple, of wide substrate scope, and remarkably can be efficiently carried out as a one‐pot process with no loss of overall yield or diastereoselectivity.

The First Observation of Hidden Hysteresis in an Iron(III) Spin‐Crossover Complex

By Theerapoom Boonprab, Seok J. Lee, Shane G. Telfer, Keith S. Murray, Wasinee Phonsri, Guillaume Chastanet, Eric Collet, Elzbieta Trzop, Guy N. L. Jameson, Phimphaka Harding, David J. Harding from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Light revealing: Thermal and optical switching in an iron(III) spin‐crossover complex reveals a hidden hysteresis of 30 K. The results show that FeIII spin‐crossover complexes can be just as effective as FeII systems, and with the advantage of being air‐stable, they are suited for use in molecular electronics. Abstract Molecular magnetic switches are expected to form the functional components of future nanodevices. Herein we combine detailed (photo‐) crystallography and magnetic studies to reveal the unusual switching properties of an iron(III) complex, between low (LS) and high (HS) spin states. On cooling, it exhibits a partial thermal conversion associated with a reconstructive phase transition from a [HS‐HS] to a [LS‐HS] phase with a hysteresis of 25 K. Photoexcitation at low temperature allows access to a [LS‐LS] phase, never observed at thermal equilibrium. As well as reporting the first iron(III) spin crossover complex to exhibit reverse‐LIESST (light‐induced excited spin state trapping), we also reveal a hidden hysteresis of 30 K between the hidden [LS‐LS] and [HS‐LS] phases. Moreover, we demonstrate that FeIII spin‐crossover (SCO) complexes can be just as effective as FeII systems, and with the advantage of being air‐stable, they are ideally suited for use in molecular electronics.

Engineered Peptide Macrocycles Can Inhibit Matrix Metalloproteinases with High Selectivity

By Khan Maola, Jonas Wilbs, Jeremy Touati, Michal Sabisz, Xu‐Dong Kong, Alice Baumann, Kaycie Deyle, Christian Heinis from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

The selective inhibition of individual matrix metalloproteinase has been a great challenge due to high structural conservation in the catalytic domains and shallow substrate binding sites. Herein, we show that inhibitors with high selectivity for specific MMPs can be developed based on peptide macrocycles. Abstract Matrix metalloproteinases (MMPs) are zinc‐dependent endopeptidases at the intersection of health and disease due to their involvement in processes such as tissue repair and immunity as well as cancer and inflammation. Because of the high structural conservation in the catalytic domains and shallow substrate binding sites, selective, small‐molecule inhibitors of MMPs have remained elusive. In a tour‐de‐force peptide engineering approach combining phage‐display selections, rational design of enhanced zinc chelation, and d‐amino acid screening, we succeeded in developing a first synthetic MMP‐2 inhibitor that combines high potency (Ki=1.9±0.5 nm), high target selectivity, and proteolytic stability, and thus fulfills all the required qualities for in cell culture and in vivo application. Our work suggests that selective MMP inhibition is achievable with peptide macrocycles and paves the way for developing specific inhibitors for application as chemical probes and potentially therapeutics.

Developing A “Polysulfide‐Phobic” Strategy to Restrain Shuttle Effect in Lithium–Sulfur Batteries

By Yibo He, Yu Qiao, Zhi Chang, Xin Cao, Min Jia, Ping He, Haoshen Zhou from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

A novel “polysulfide‐phobic” strategy was proposed to restrain shuttle effect in Li–S batteries. Owing to the intrinsic electronegativity of polysulfide anions, the polar materials anchored with polysulfides can evolve into a “polysulfide‐phobic” surface and performed strong repulsion effect on the free polysulfides anions, which was demonstrated by the advanced time/space‐resolved operando Raman evidences. Abstract Inspired by hydrophobic interface, a novel design of “polysulfide‐phobic” interface was proposed and developed to restrain shuttle effect in lithium–sulfur batteries. Two‐dimensional VOPO4 sheets with adequate active sites were employed to immobilize the polysulfides through the formation of a V−S bond. Moreover, owing to the intrinsic Coulomb repulsion between polysulfide anions, the surface anchored with polysulfides can be further evolved into a “polysulfide‐phobic” interface, which was demonstrated by the advanced time/space‐resolved operando Raman evidences. In particular, by introducing the “polysulfide‐phobic” surface design into separator fabrication, the lithium–sulfur battery performed a superior long‐term cycling stability. This work expands a novel strategy to build a “polysulfide‐phobic” surface by “self‐defense” mechanism for suppressing polysulfides shuttle, which provides new insights and opportunities to develop advanced lithium–sulfur batteries.

Silica‐Supported Molybdenum Oxo Alkylidenes: Bridging the Gap between Internal and Terminal Olefin Metathesis

By Margherita Pucino, Feng Zhai, Christopher P. Gordon, Deni Mance, Amir H. Hoveyda, Richard R. Schrock, Christophe Copéret from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Latest but not least: A silica‐supported molybdenum oxo alkylidene complex displays high activity in olefin homometathesis of both terminal and internal olefins. This finding contrasts with the lower activities of the corresponding reported tungsten oxo, molybdenum imido, and tungsten imido complexes. Abstract Grafting a molybdenum oxo alkylidene on silica (partially dehydroxylated at 700 °C) affords the first example of a well‐defined silica‐supported Mo oxo alkylidene, which is an analogue of the putative active sites in heterogeneous Mo‐based metathesis catalysts. In contrast to its tungsten analogue, which shows poor activity towards terminal olefins because of the formation of a stable off‐cycle metallacyclobutane intermediate, the Mo catalyst shows high metathesis activity for both terminal and internal olefins that is consistent with the lower stability of Mo metallacyclobutane intermediates. This Mo oxo metathesis catalyst also outperforms its corresponding neutral silica‐supported Mo and W imido analogues.

Cysteine‐Selective Phosphonamidate Electrophiles for Modular Protein Bioconjugations

By Marc‐André Kasper, Maria Glanz, Andreas Stengl, Martin Penkert, Simon Klenk, Tom Sauer, Dominik Schumacher, Jonas Helma, Eberhard Krause, M. Cristina Cardoso, Heinrich Leonhardt, Christian P. R. Hackenberger from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Staudinger—Ready—Go! Ethynylphosphonamidates can be chemoselectively incorporated into a given molecule through a Staudinger‐phosphonite reaction, and they react specifically with cysteine residues on proteins to give thiol adducts that are stable under physiological conditions. This enables the facile fusion of complex molecules to proteins. Abstract We describe a new technique in protein synthesis that extends the existing repertoire of methods for protein modification: A chemoselective reaction that induces reactivity for a subsequent bioconjugation. An azide‐modified building block reacts first with an ethynylphosphonite through a Staudinger‐phosphonite reaction (SPhR) to give an ethynylphosphonamidate. The resulting electron‐deficient triple bond subsequently undergoes a cysteine‐selective reaction with proteins or antibodies. We demonstrate that ethynylphosphonamidates display excellent cysteine‐selective reactivity combined with superior stability of the thiol adducts, when compared to classical maleimide linkages. This turns our technique into a versatile and powerful tool for the facile construction of stable functional protein conjugates.

Harvesting the Vibration Energy of BiFeO3 Nanosheets for Hydrogen Evolution

By Huilin You, Zheng Wu, Luohong Zhang, Yiran Ying, Yan Liu, Linfeng Fei, Xinxin Chen, Yanmin Jia, Yaojin Wang, Feifei Wang, Sheng Ju, Jinli Qiao, Chi‐Hang Lam, Haitao Huang from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Good vibrations! BiFeO3 can serve as a piezocatalyst for hydrogen production by harvesting vibration energy from the environment. The strong piezoelectric field induced by mechanical vibrations tilts the conduction band of BiFeO3, making it more negative than the H2/H2O redox potential, thus enabling hydrogen evolution (see picture). Abstract In this study, mechanical vibration is used for hydrogen generation and decomposition of dye molecules, with the help of BiFeO3 (BFO) square nanosheets. A high hydrogen production rate of ≈124.1 μmol g−1 is achieved under mechanical vibration (100 W) for 1 h at the resonant frequency of the BFO nanosheets. The decomposition ratio of Rhodamine B dye reaches up to ≈94.1 % after mechanical vibration of the BFO catalyst for 50 min. The vibration‐induced catalysis of the BFO square nanosheets may be attributed to the piezocatalytic properties of BFO and the high specific surface area of the nanosheets. The uncompensated piezoelectric charges on the surfaces of BFO nanosheets induced by mechanical vibration result in a built‐in electric field across the nanosheets. Unlike a photocatalyst for water splitting, which requires a proper band edge position for hydrogen evolution, such a requirement is not needed in piezocatalytic water splitting, where the band tilting under the induced piezoelectric field will make the conduction band of BFO more negative than the H2/H2O redox potential (0 V) for hydrogen generation.

Sub‐Micromolar Pulse Dipolar EPR Spectroscopy Reveals Increasing CuII‐labelling of Double‐Histidine Motifs with Lower Temperature

By Joshua L. Wort, Katrin Ackermann, Angeliki Giannoulis, Alan J. Stewart, David G. Norman, Bela E. Bode from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Quantitative nanomolar pulse EPR spectroscopy demonstrates that CuII–NTA binds double‐histidine (d‐His) motifs with nanomolar affinity making it an attractive genetically encoded protein spin label. This approach is particularly useful for high distance resolution and for the study of proteins containing essential cysteines. Abstract Electron paramagnetic resonance (EPR) distance measurements are making increasingly important contributions to the studies of biomolecules by providing highly accurate geometric constraints. Combining double‐histidine motifs with CuII spin labels can further increase the precision of distance measurements. It is also useful for proteins containing essential cysteines that can interfere with thiol‐specific labelling. However, the non‐covalent CuII coordination approach is vulnerable to low binding‐affinity. Herein, dissociation constants (KD) are investigated directly from the modulation depths of relaxation‐induced dipolar modulation enhancement (RIDME) EPR experiments. This reveals low‐ to sub‐μm CuII KDs under EPR distance measurement conditions at cryogenic temperatures. We show the feasibility of exploiting the double‐histidine motif for EPR applications even at sub‐μm protein concentrations in orthogonally labelled CuII–nitroxide systems using a commercial Q‐band EPR instrument.

Elucidating the Doping Effect on the Electronic Structure of Thiolate‐Protected Silver Superatoms by Photoelectron Spectroscopy

By Kuenhee Kim, Keisuke Hirata, Katsunosuke Nakamura, Hirokazu Kitazawa, Shun Hayashi, Kiichirou Koyasu, Tatsuya Tsukuda from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

Central exchange: The heteroatom doping effect on superatomic orbitals in [XAg24(SR)18]− (X=Ag, Au) and [YAg24(SR)18]2− (Y=Pd, Pt) was examined using gas‐phase photoelectron spectroscopy. The adiabatic electron affinity of [XAg24(SR)18] is reduced by approximately 1.4 eV upon replacement of the central X+ cation by a neutral Y atom. Abstract Gas‐phase photoelectron spectroscopy (PES) was conducted on [XAg24(SPhMe2)18]− (X=Ag, Au) and [YAg24(SPhMe2)18]2− (Y=Pd, Pt), which have a formal superatomic core (X@Ag12)5+ or (Y@Ag12)4+ with icosahedral symmetry. PES results show that superatomic orbitals in the (Au@Ag12)5+ core remain unshifted with respect to those in the (Ag@Ag12)5+ core, whereas the orbitals in the (Y@Ag12)4+ (Y = Pd, Pt) core shift up in energy by about 1.4 eV. The remarkable doping effect of a single Y atom (Y=Pd, Pt) on the electronic structure of the chemically modified (Ag@Ag12)5+ superatom was reproduced by theoretical calculations on simplified model systems and was ascribed to 1) the weaker binding of valence electrons in Y@(Ag+)12 compared to Ag+@(Ag+)12 due to the reduction in formal charge of the core potential, and 2) the upward shift of the apparent vacuum level due to the presence of a repulsive Coulomb barrier between [YAg24(SPhMe2)18]− and electron.

Panče Naumov

By from Wiley: Angewandte Chemie International Edition: Table of Contents. Published on Aug 09, 2019.

“I would have liked to have discovered the atom in physics, the gene in biology, and the chemical bond in chemistry. When I′m frustrated, I plant seeds and grow herbs in my conservatory …” Find out more about Pance Naumov in his Author Profile.

Nanomaterials Innovation

By Yongfei Wang, Shulei Chou, Zhiqiang Zhang from Wiley: Small: Table of Contents. Published on Aug 09, 2019.

Masthead: (Small 32/2019)

By from Wiley: Small: Table of Contents. Published on Aug 09, 2019.

Nanomaterials Innovation: Nanomaterials Innovation (Small 32/2019)

By Yongfei Wang, Shulei Chou, Zhiqiang Zhang from Wiley: Small: Table of Contents. Published on Aug 09, 2019.

The year 2018 marked the 70th anniversary of the University of Science and Technology Liaoning (USTL) in Liaoning Province, China. To celebrate the outstanding development, the 2018 International Conference of Novel Function Materials (ICNFM2018) was held from the 16th to 18th of September 2018 in Anshan China. In article number 1902246, Yongfei Wang, Shulei Chou, and Zhiqiang Zhang introduce the Special Issue.

Photodynamic Therapy: Boron Dipyrromethene Nano‐Photosensitizers for Anticancer Phototherapies (Small 32/2019)

By Wen Sun, Xueze Zhao, Jiangli Fan, Jianjun Du, Xiaojun Peng from Wiley: Small: Table of Contents. Published on Aug 09, 2019.

In article number 1804927, Jiangli Fan and co‐workers comprehensively survey the recent development of boron dipyrromethene nanophotosensitizers for cancer treatment via photodynamic therapy (PDT), photothermal therapy (PTT), and the combination of PDT and PTT. Their detailed applications in vitro and in vivo are discussed, and their potential for new tumor phototherapies are highlighted.

Wearable Electronics: Buckled Structures: Fabrication and Applications in Wearable Electronics (Small 32/2019)

By Xiaoyu Hu, Yuanyuan Dou, Jingjing Li, Zunfeng Liu from Wiley: Small: Table of Contents. Published on Aug 09, 2019.

The dawn of the age of wearable electronics: buckling structures, which are widely used in nature, provide the required deformability of wearable electronic devices. In article number 1804805, Zunfeng Liu and co‐workers provide fundamental insights into recent advances of fabrication of buckling structures and their applications in wearable electronics. Challenges and future perspectives for buckled electronics are briefly discussed.

Three‐Terminal Artificial Synapses: Recent Progress in Three‐Terminal Artificial Synapses: From Device to System (Small 32/2019)

By Hong Han, Haiyang Yu, Huanhuan Wei, Jiangdong Gong, Wentao Xu from Wiley: Small: Table of Contents. Published on Aug 09, 2019.

An electronic device that emulates synaptic plasticity is essential for building up a neuromorphic system. In article number 1900695, Wentao Xu and co‐workers review recent progress in the design and fabrication of three‐terminal artificial synapses, and their applications in bioinspired systems such as tactile‐perception and light‐sensing actuation.

Asymmetric Catalysis: Asymmetric Catalysis within the Chiral Confined Space of Metal–Organic Architectures (Small 32/2019)

By Xuezhao Li, Jinguo Wu, Cheng He, Qingtao Meng, Chunying Duan from Wiley: Small: Table of Contents. Published on Aug 09, 2019.

In article number 1804770, Chunying Duan and co‐workers comprehensively survey recent asymmetric catalysis processes of metal–organic cages (MOCs) and metal–organic frameworks (MOFs) with chiral confined space that is analogous to the binding pocket of enzymes. The spatial constraints and shielding effects exhibit an ideal working yard to accelerate a series of novel asymmetric transformations with one‐chiral center or even multi‐chiral centers by modulating the orientational and rotational freedom of the encapsulated substrates. The commonality and differences of chiral MOCs‐ and MOFs‐based asymmetric catalysis are discussed to present a connection between these two important fields and share design concepts and applications that may be useful to both in asymmetric transformations.

Biomacromolecule‐Functionalized AIEgens for Advanced Biomedical Studies

By Feng Wu, Xia Wu, Zhijuan Duan, Yu Huang, Xiaoding Lou, Fan Xia from Wiley: Small: Table of Contents. Published on Aug 09, 2019.

The design principles and functionalized methods of biomacromolecule functionalized AIEgens are introduced herein. They include nucleic acid‐, peptide‐, glycan‐, and lipid‐functionalized AIEgens, which are highly desired for biomedical study, biotechnology, bioinformatics, and clinical science. Through illustrating their functional mechanisms and biological applications, it may be a guide for researchers from various fields. Abstract The advances in bioinformatics and biomedicine have promoted the development of biomedical imaging and theranostic systems to respectively extend the endogenous biomarker imaging with high contrast and enhance the therapeutic effect with high efficiency. The emergence of biomacromolecule‐functionalized aggregation‐induced emitters (AIEgens), utilizing AIEgens, and biomacromolecules (nucleic acids, peptides, glycans, and lipids), displays specific targeting ability to cancer cell, improved biocompatibility, reduced toxicity, enhanced therapeutic effect, and so forth. This review summarizes the rational design of biomacromolecule‐functionalized AIEgens and their biomedical applications in recent ten years, including high‐resolution optical imaging of cell, tissue, and small animal model with low background; the biomarker detection for early diagnosis and prognosis; the delivery and monitoring of prodrugs; image‐guide photodynamic therapy and its combination with chemotherapy. Through illustrating their functional mechanisms and application, it is hoped that this review would open up a completely new train of research thought for attracted researchers in various fields.

Chemical Properties, Structural Properties, and Energy Storage Applications of Prussian Blue Analogues

By Wei‐Jie Li, Chao Han, Gang Cheng, Shu‐Lei Chou, Hua‐Kun Liu, Shi‐Xue Dou from Wiley: Small: Table of Contents. Published on Aug 09, 2019.

This Review provides a comprehensive overview of the latest research progress on Prussian blue analogues (PBAs), including the synthesis methods, structural and chemical properties of PBAs, various applications for these PBAs, and the effects of their structural and chemical properties on material synthesis and applications. Finally, some personal viewpoints on the challenges and outlook for PBAs application are included. Abstract Prussian blue analogues (PBAs, A2T[M(CN)6], A = Li, K, Na; T = Fe, Co, Ni, Mn, Cu, etc.; M = Fe, Mn, Co, etc.) are a large family of materials with an open framework structure. In recent years, they have been intensively investigated as active materials in the field of energy conversion and storage, such as for alkaline‐ion batteries (lithium‐ion, LIBs; sodium‐ion, NIB; and potassium‐ion, KIBs), and as electrochemical catalysts. Nevertheless, few review papers have focused on the intrinsic chemical and structural properties of Prussian blue (PB) and its analogues. In this Review, a comprehensive insight into the PBAs in terms of their structural and chemical properties, and the effects of these properties on their materials synthesis and corresponding performance is provided.

Nonaqueous Sodium‐Ion Full Cells: Status, Strategies, and Prospects

By Yu‐Bin Niu, Ya‐Xia Yin, Yu‐Guo Guo from Wiley: Small: Table of Contents. Published on Aug 09, 2019.

Sodium‐ion full cells with low cost and abundant resource are promising to satisfy the urgent demand of large‐scale energy storage, yet their developments suffer from challenges of interfacial characteristics. Here, their recent advances in various electrolytes are summarized, and diverse strategies including tailoring interface, matching capacity, optimizing electrolyte as well as compensating sodium to drive the development of the whole industry are addressed. Abstract With ever‐increasing efforts focused on basic research of sodium‐ion batteries (SIBs) and growing energy demand, sodium‐ion full cells (SIFCs), as unique bridging technology between sodium‐ion half‐cells (SIHCs) and commercial batteries, have attracted more and more interest and attention. To promote the development of SIFCs in a better way, it is essential to gain a systematic and profound insight into their key issues and research status. This Review mainly focuses on the interface issues, major challenges, and recent progresses in SIFCs based on diversified electrolytes (i.e., nonaqueous liquid electrolytes, quasi‐solid‐state electrolytes, and all‐solid‐state electrolytes) and summarizes the modification strategies to improve their electrochemical performance, including interface modification, cathode/anode matching, capacity ratio, electrolyte optimization, and sodium compensation. Outlooks and perspectives on the future research directions to build better SIFCs are also provided.

Resistive Switching Behavior in Ferroelectric Heterostructures

By Zhan Jie Wang, Yu Bai from Wiley: Small: Table of Contents. Published on Aug 09, 2019.

The relationship between resistive switching (RS) ratio and ferroelectricity and conductivity in ferroelectric heterostructures is reviewed based on literature. The ferroelectric heterostructures with good ferroelectricity and conductivity exhibit high RS ratio. It can be expected that the use of lead‐free ferroelectric materials, ferroelectric nanocomposites, and multifield coupling are effective ways to further improve the RS ratio. Abstract Resistive random‐access memory (RRAM) is a promising candidate for next‐generation nonvolatile random‐access memory protocols. The information storage in RRAM is realized by the resistive switching (RS) effect. The RS behavior of ferroelectric heterostructures is mainly controlled by polarization‐dominated and defect‐dominated mechanisms. Under certain conditions, these two mechanisms can have synergistic effects on RS behavior. Therefore, RS performance can be effectively improved by optimizing ferroelectricity, conductivity, and interfacial structures. Many methods have been studied to improve the RS performance of ferroelectric heterostructures. Typical approaches include doping elements into the ferroelectric layer, controlling the oxygen vacancy concentration and optimizing the thickness of the ferroelectric layer, and constructing an insertion layer at the interface. Here, the mechanism of RS behavior in ferroelectric heterostructures is briefly introduced, and the methods used to improve RS performance in recent years are summarized. Finally, existing problems in this field are identified, and future development trends are highlighted.

Multishelled Transition Metal‐Based Microspheres: Synthesis and Applications for Batteries and Supercapacitors

By Yang Liu, Xiangcun Li, Weiming Shen, Yan Dai, Wei Kou, Wenji Zheng, Xiaobin Jiang, Gaohong He from Wiley: Small: Table of Contents. Published on Aug 09, 2019.

Numerous unique properties and functionalities have prompted the design and engineering of multishelled transition metal‐based microspheres. Here, a detailed overview of the various synthetic strategies is given including hard‐templating, soft‐templating, and free‐template methods, and insight is offered into the great promise for energy storage systems in the application of lithium/sodium batteries, supercapacitors, and lithium‐surfer batteries. Abstract With the rapid growth of material innovations, multishelled hollow nanostructures are of tremendous interest due to their unique structural features and attractive physicochemical properties. Continued effort has been made in the geometric manipulation, composition complexity, and construction diversity of this material, expanding its applications. Energy storage technology has benefited from the large surface area, short transport path, and excellent buffering ability of the nanostructures. In this work, the general synthesis of multishelled hollow structures, especially with architecture versatility, is summarized. A wealth of attractive properties is also discussed for a wide area of potential applications based on energy storage systems, including Li‐ion/Na‐ion batteries, supercapacitors, and Li–S batteries. Finally, the emerging challenges and outlook for multishelled hollow structures are mentioned.

Boron Dipyrromethene Nano‐Photosensitizers for Anticancer Phototherapies

By Wen Sun, Xueze Zhao, Jiangli Fan, Jianjun Du, Xiaojun Peng from Wiley: Small: Table of Contents. Published on Aug 09, 2019.

Boron dipyrromethene (BODIPY) nano‐photosensitizers are equipped with enhanced water solubility, biocompatibility, and tumor accumulation via the enhanced permeability and retention (EPR) effect. In addition, their excellent photostability and large molar extinction coefficient in the near infrared (NIR) region ensure a special phototherapy effect toward tumors. This review focuses on the design and preparation of BODIPY containing nano‐photosensitizers for anticancer phototherapy. Abstract As traditional phototherapy agents, boron dipyrromethene (BODIPY) photosensitizers have attracted increasing attention due to their high molar extinction coefficients, high phototherapy efficacy, and excellent photostability. After being formed into nanostructures, BODIPY‐containing nano‐photosensitizers show enhanced water solubility and biocompatibility as well as efficient tumor accumulation compared to BODIPY molecules. Hence, BODIPY nano‐photosensitizers demonstrate a promising potential for fighting cancer. This review contains three sections, classifying photodynamic therapy (PDT), photothermal therapy (PTT), and the combination of PDT and PTT based on BODIPY nano‐photosensitizers. It summarizes various BODIPY nano‐photosensitizers, which are prepared via different approaches including molecular precipitation, supramolecular interactions, and polymer encapsulation. In each section, the design strategies and working principles of these BODIPY nano‐photosensitizers are highlighted. In addition, the detailed in vitro and in vivo applications of these recently developed nano‐photosensitizers are discussed together with future challenges in this field, highlighting the potential of these promising nanoagents for new tumor phototherapies.

Buckled Structures: Fabrication and Applications in Wearable Electronics

By Xiaoyu Hu, Yuanyuan Dou, Jingjing Li, Zunfeng Liu from Wiley: Small: Table of Contents. Published on Aug 09, 2019.

This review focuses on the fabrication of buckling structures and their applications in wearable electronics. The contents of this review are briefly summarized in the pie chart below. The patterns in the center represent buckles. The arrows on the periphery suggest that research in these fields is closely related. Abstract Wearable electronics have attracted a tremendous amount of attention due to their many potential applications, such as personalized health monitoring, motion detection, and smart clothing, where electronic devices must conformably form contacts with curvilinear surfaces and undergo large deformations. Structural design and material selection have been the key factors for the development of wearable electronics in the recent decades. As one of the most widely used geometries, buckling structures endow high stretchability, high mechanical durability, and comfortable contact for human–machine interaction via wearable devices. In addition, buckling structures that are derived from natural biosurfaces have high potential for use in cost‐effective and high‐grade wearable electronics. This review provides fundamental insights into buckling fabrication and discusses recent advancements for practical applications of buckled electronics, such as interconnects, sensors, transistors, energy storage, and conversion devices. In addition to the incorporation of desired functions, the simple and consecutive manipulation and advanced structural design of the buckled structures are discussed, which are important for advancing the field of wearable electronics. The remaining challenges and future perspectives for buckled electronics are briefly discussed in the final section.

Key Aspects of Lithium Metal Anodes for Lithium Metal Batteries

By Zahid Ali Ghazi, Zhenhua Sun, Chengguo Sun, Fulai Qi, Baigang An, Feng Li, Hui‐Ming Cheng from Wiley: Small: Table of Contents. Published on Aug 09, 2019.

Lithium (Li) metal anode is broadly recognized as an excellent candidate for nextgeneration energy storage devices owing to its high specific energy density. In this Review, a conceptual understanding about the key aspects of Li metal anode is provided, the most recent advancements in Li metal battery technology are outlined and suggestions for future research on Li anodes are presented. Abstract Rechargeable batteries are considered promising replacements for environmentally hazardous fossil fuel‐based energy technologies. High‐energy lithium‐metal batteries have received tremendous attention for use in portable electronic devices and electric vehicles. However, the low Coulombic efficiency, short life cycle, huge volume expansion, uncontrolled dendrite growth, and endless interfacial reactions of the metallic lithium anode are major obstacles in their commercialization. Extensive research efforts have been devoted to address these issues and significant progress has been made by tuning electrolyte chemistry, designing electrode frameworks, discovering nanotechnology‐based solutions, etc. This Review aims to provide a conceptual understanding of the current issues involved in using a lithium metal anode and to unveil its electrochemistry. The most recent advancements in lithium metal battery technology are outlined and suggestions for future research to develop a safe and stable lithium anode are presented.

Design, Performance, and Application of Thermoelectric Nanogenerators

By Ding Zhang, Yuanhao Wang, Ya Yang from Wiley: Small: Table of Contents. Published on Aug 09, 2019.

Thermoelectric nanogenerators (TEGs) for energy harvesting provide an ideal way to realize self‐powered operation of electronics and play an increasingly important role in harvesting and converting heat into electric energy. The development of TEGs including materials optimization, structural designs, and potential applications, even the opportunities, challenges, and future development direction, is analyzed and summarized. Abstract Thermal energy harvesting from the ambient environment through thermoelectric nanogenerators (TEGs) is an ideal way to realize self‐powered operation of electronics, and even relieve the energy crisis and environmental degradation. As one of the most significant energy‐related technologies, TEGs have exhibited excellent thermoelectric performance and played an increasingly important role in harvesting and converting heat into electric energy, gradually becoming one of the hot research fields. Here, the development of TEGs including materials optimization, structural designs, and potential applications, even the opportunities, challenges, and the future development direction, is analyzed and summarized. Materials optimization and structural designs of flexibility for potential applications in wearable electronics are systematically discussed. With the development of flexible and wearable electronic equipment, flexible TEGs show increasingly great application prospects in artificial intelligence, self‐powered sensing systems, and other fields in the future.

Carbon Dots‐in‐Matrix Boosting Intriguing Luminescence Properties and Applications

By Jiyang Li, Bolun Wang, Hongyue Zhang, Jihong Yu from Wiley: Small: Table of Contents. Published on Aug 09, 2019.

Embedding carbon dots (CDs) in matrix endow CDs intriguing luminescence properties and applications. Highlighting the crucial role of matrix, the recent advancements in synthesis, luminescence, and applications of CDs‐based composite materials are reviewed. In addition, the perspectives for future development are noted. Abstract As a new class of luminescent nanomaterials, carbon dots (CDs) have aroused significant interest because of their fascinating photoluminescence properties and potential applications in biological, optoelectronic, and energy‐related fields. Strikingly, embedding CDs in host matrices endow them with intriguing luminescent properties, in particular, room temperature phosphorescence and thermally activated delayed fluorescence, due to the confinement effect of the host matrix and the H‐bonding interactions between CDs and the matrix. Here, the state‐of‐the‐art strategies for introducing CDs in various host matrices are summarized, such as nanoporous materials, polyvinyl alcohol, polyurethane, potash alum, layered double hydroxides, amorphous silica, etc. The resultant luminescent properties of the composites and their emission mechanisms are discussed. Their applications in bioimaging, drug delivery/release, sensing, and anticounterfeiting are also presented. Finally, current problems and challenges of CDs‐based composites are noted for future development of such luminescent materials.

Biomolecule‐Functionalized Solid‐State Ion Nanochannels/Nanopores: Features and Techniques

By Defang Ding, Pengcheng Gao, Qun Ma, Dagui Wang, Fan Xia from Wiley: Small: Table of Contents. Published on Aug 09, 2019.

Biomolecule‐functionalized solid‐state ion nanochannels/nanopores combine both the characteristics of biomolecules and the properties of solid‐state ion nanochannels/nanopores. Ultimately, two features—specificity and signal amplification—are generated, which are strongly associated with the applications in sensing, transport, and energy conversion. The corresponding functionalization techniques related to surface chemistry are also with good developments. Abstract Solid‐state ion nanochannels/nanopores, the biomimetic products of biological ion channels, are promising materials in real‐world applications due to their robust mechanical and controllable chemica