http://onlinelibrary.wiley.com/rss/journal/10.1002/(ISSN)1521-4095

Two regioisomeric COFs incorporating the thieno[3,2-b]thiophene moiety are synthesized for photocatalytic H2O2 production. The β-isomer exhibits exceptional performance compared to the α-isomeric counterpart due to optimized electron distribution, enhance charge transfer efficiency, and precise alignment of excited-state electrons with the ORR active site, demonstrating the great potential of leveraging regioisomerism in COF design.

Covalent organic frameworks (COFs) are emerging as a transformative platform for photocatalytic hydrogen peroxide (H2O2) production due to their highly ordered structures, intrinsic porosity, and molecular tunability. Despite their potential, the inefficient utilization of photogenerated charge carriers in COFs significantly restrains their photocatalytic efficiency. This study presents two regioisomeric COFs, α-TT-TDAN COF and β-TT-TDAN COF, both incorporating thieno[3,2-b]thiophene moieties, to investigate the influence of regioisomerism on the excited electron distribution and its impact on photocatalytic performance. The β-TT-TDAN COF demonstrates a remarkable solar-to-chemical conversion efficiency of 1.35%, outperforming its α-isomeric counterpart, which is merely 0.44%. Comprehensive spectroscopic and computational investigations reveal the critical role of subtle substitution change in COFs on their electronic properties. This structural adjustment intricately connects molecular structure to charge dynamics, enabling precise regulation of electron distribution, efficient charge separation and transport, and localization of excited electrons at active sites. Moreover, this finely tuned interplay significantly enhances the efficiency of the oxygen reduction reaction. These findings establish a new paradigm in COF design, offering a molecular-level strategy to advance COFs and reticular materials toward highly efficient solar-to-chemical energy conversion.

This study presents RuNPs-RuCrAPs-N-C, a novel electrocatalyst incorporating Ru nanoparticles (RuNPs), single atoms, and Ru–Cr atomic pairs (RuCrAps) on nitrogen-doped carbon, exhibiting exceptional alkaline hydrogen evolution reaction (HER) activity. RuCrAPs modify the electronic structure of RuNPs as active sites through the optimised electronic metal support interaction (EMSI) and enhanced water adsorption and dissociation.

Precisely optimizing the electronic metal support interaction (EMSI) of the electrocatalysts and tuning the electronic structures of active sites are crucial for accelerating water adsorption and dissociation kinetics in alkaline hydrogen evolution reaction (HER). Herein, an effective strategy is applied to modify the electronic structure of Ru nanoparticles (RuNPs) by incorporating Ru single atoms (RuSAs) and Ru and Cr atomic pairs (RuCrAPs) onto a nitrogen-doped carbon (N–C) support through optimized EMSI. The resulting catalyst, RuNPs-RuCrAPs-N-C, shows exceptional performance for alkaline HER, achieving a six times higher turnover frequency (TOF) of 13.15 s⁻¹ at an overpotential of 100 mV, compared to that of commercial Pt/C (2.07 s⁻¹). Additionally, the catalyst operates at a lower overpotential at a current density of 10 mA·cm⁻2 (η10 = 31 mV), outperforming commercial Pt/C (η10 = 34 mV). Experimental results confirm that the RuCrAPs modified RuNPs are the main active sites for the alkaline HER, facilitating the rate-determining steps of water adsorption and dissociation. Moreover, the Ru–Cr interaction also plays a vital role in modulating hydrogen desorption. This study presents a synergistic approach by rationally combining single atoms, atomic pairs, and nanoparticles with optimized EMSI effects to advance the development of efficient electrocatalysts for alkaline HER.

In situ magnetism measurement is employed to investigate the magnetic/electronic structure evolution in the Li-rich cathode. The magnetization changes demonstrate that charge storage behavior originates from synergistic transition metal spin-state variation and π-to-σ interaction evolution, and further elucidate the internal origin of capacity decay during cycling. The Mn─O orbital model provides potential criteria for oxygen redox, guiding rational design of anionic redox-based cathodes.

Oxide ions in lithium-rich layered oxides can store charge at high voltage and offer a viable route toward the higher energy density batteries. However, the underlying oxygen redox mechanism in such materials still remains elusive at present. In this work, a precise in situ magnetism measurement is employed to monitor real-time magnetization variation associated with unpaired electrons in Li1.2Mn0.6Ni0.2O2 cathode material, enabling the investigation on magnetic/electronic structure evolution in electrochemical cycling. The magnetization gradually decreases except for a weak upturn above 4.6 V during the initial charging process. According to the comprehensive analyses of various in/ex situ characterizations and density functional theory (DFT) calculations, the magnetization rebound can be attributed to the interaction evolution of lattice oxygen from π-type delocalized Mn─O coupling to σ-type O─O dimerization bonding. Moreover, the magnetization amplitude attenuation after long-term cycles provides important evidence for the irreversible structure transition and capacity fading. The oxygen redox mechanism concluded by in situ magnetism characterization can be generalized to other electrode materials with an anionic redox process and provide pivotal guidance for designing advanced high-performance cathode materials.

This work proposed an efficient Yb3+-doped PEA2Cs2Pb3Br10 quasi 2D layered metal halide perovskites (2D-LMHPs) film and revealed the microscopic energy transfer process of the complex system. Moreover, an efficient and super-stable 990 nm NIR PeLED with the external quantum efficiency (EQE) up to 8.8% and a record operational lifetime of 1274 min is obtained. These findings will expand the optical properties and application potential of quasi 2D-LMHPs materials.

Quasi 2D layered metal halide perovskites (2D-LMHPs) with natural quantum wells (QWs) structure have garnered significant attention due to their excellent optoelectronic properties. Doping rare earth (RE) ions with 4f n inner shell emission levels can largely expand their optical and optoelectronic properties and realize diverse applications, but has not been reported yet. Herein, an efficient Yb3+-doped PEA2Cs2Pb3Br10 quasi 2D-LMHPs is fabricated and directly identified the Yb3+ ions in the quasi 2D-LMHPs at the atomic scale using aberration electron microscopy. The interaction between different n phases and Yb3+ ions is elucidated using ultrafast transient absorption spectroscopy and luminescent dynamics, which demonstrated efficient, different time scales and multi-channel energy transfer processes. Finally, through phase distribution manipulation and surface passivation, the optimized film exhibits a photoluminescence quantum yield of 144%. This is the first demonstration of quantum cutting emission in pure Br-based perovskite material, suppressing defect states and ion migration. The efficient and stable near-infrared light-emitting diodes (NIR LED) is fabricated with a peak external quantum efficiency (EQE) of 8.8% at 990 nm and the record lifetime of 1274 min. This work provides fresh insight into the interaction between RE ions and quasi 2D-LMHPs and extend the function and application of quasi 2D-LMHPs materials.

Artificial antiferromagnetically coupled multilayered heterostructures with tailored interlayer exchange interactions and perpendicular magnetic anisotropy hold great promise for applications such as magnetic random-access memory, magnetic sensors, and spintronics. Voltage-driven ion migration (i.e., magneto-ionics) enables post-synthesis tuning of these magnetic stacks, allowing significant modulation of the various switching events and transitions between antiferromagnetic (AFM) and ferrimagnetic (FiM) states.

Voltage-driven ion motion offers a powerful means to modulate magnetism and spin phenomena in solids, a process known as magneto-ionics, which holds great promise for developing energy-efficient next-generation micro- and nano-electronic devices. Synthetic antiferromagnets (SAFs), consisting of two ferromagnetic layers coupled antiferromagnetically via a thin non-magnetic spacer, offer advantages such as enhanced thermal stability, robustness against external magnetic fields, and reduced magnetostatic interactions in magnetic tunnel junctions. Despite its technological potential, magneto-ionic control of antiferromagnetic coupling in multilayers (MLs) has only recently been explored and remains poorly understood, particularly in systems free of platinum-group metals. In this work, room-temperature voltage control of Ruderman–Kittel–Kasuya–Yosida (RKKY) interactions in Co/Ni-based SAFs is achieved. Transitions between ferrimagnetic (uncompensated) and antiferromagnetic (fully compensated) states is observed, as well as significant modulation of the RKKY bias field offset, emergence of additional switching events, and formation of skyrmion-like or pinned domain bubbles under relatively low gating voltages. These phenomena are attributed to voltage-driven oxygen migration in the MLs, as confirmed through microscopic and spectroscopic analyses. This study underscores the potential of voltage-triggered ion migration as a versatile tool for post-synthesis tuning of magnetic multilayers, with potential applications in magnetic-field sensing, energy-efficient memories and spintronics.

This study fabricates a large-area multicolor rare-earth afterglow film via electrospinning, integrating ZnS and tricolor rare-earth phosphors to achieve ultra-long afterglow (>30 h) and tunable emissions. The film exhibits thermoluminescence, environmental stability, and light-capturing capabilities, enabling applications in fire-rescue gear, greenhouses, and energy-efficient tunnel/garage lighting. Its scalable production and cost-effectiveness advance energy-saving technologies in agriculture, safety, and urban infrastructure.

Rare-earth afterglow materials, with their unique light-storage properties, show great promise for diverse applications. However, their broader applicability is constrained by challenges such as poor solvent compatibility, limited luminescent efficiency, and monochromatic emissions. In this study, these limitations are addressed by blending ZnS with various rare-earth phosphors including (Sr0.75Ca0.25)S:Eu2+; SrAl2O4:Eu2+, Dy3+ and Sr2MgSi2O7:Eu2+, Dy3+ to modulate deep trap mechanisms and significantly enhance both the afterglow and light capture capabilities. Using electrospinning, a large-area (0.4 m × 3 m) afterglow film is successfully fabricated with tunable colors and an extended afterglow duration exceeding 30 h. This film demonstrates thermoluminescence, enabling potential integration into fire-rescue protective clothing for enhanced emergency visibility. In greenhouse settings, it effectively supports chlorophyll synthesis and optimizes conditions for plant growth over a 24-h cycle. For tunnel and garage applications, the film captures and stores light from vehicle headlights at distances of up to 70 meters. The scalability and cost-effectiveness of this afterglow film underscore its considerable potential for real-world applications across multiple fields, marking a significant advancement in sustainable illumination technology.

A natural binary electrolyte additive is designed to achieve an enhanced interfacial molecule adsorption layer for Zn protection via reshaping the electric double-layer structure. Consequently, the hydrogen evolution reaction is suppressed and a robust inorganic solid electrolyte interphase is constructed for dendrite-free Zn plating. The zinc ion hybrid capacitor with binary additive demonstrates an exceptional lifespan of over 100 000 cycles.

Aqueous zinc ion batteries (AZIBs) face challenges due to the limited interface stability of Zn anode, which includes uncontrolled hydrogen evolution reaction (HER) and excessive dendrite growth. In this study, a natural binary additive composed of saponin and anisaldehyde is introduced to create a stable interfacial adsorption layer for Zn protection via reshaping the electric double layer (EDL) structure. Saponin with rich hydroxyl and carboxyl groups serves as “anchor points”, promoting the adsorption of anisaldehyde through intermolecular hydrogen bonding. Meanwhile, anisaldehyde, with a unique aldehyde group, enhances HER suppression by preferentially facilitating electrocatalytic coupling with H* in the EDL, leading to the formation of a robust inorganic solid electrolyte interphase that prevents dendrite formation, and structural evolution of anisaldehyde during Zn deposition process is verified. As a result, the Zn||Zn symmetric cells present an ultra-long cycling lifespan of 3 400 h at 1 mA cm−2 and 1 700 h at 10 mA cm−2. Even at the current density of 20 mA cm−2, the cells demonstrate reversible operations for 450 h. Furthermore, Zn-ion hybrid capacitors exhibit a remarkable lifespan of 100 000 cycles. This work presents a simple synergetic strategy to enhance anode/electrolyte interfacial stability, highlighting its potential for Zn anode protection in high-performance AZIBs.

RuNi composites are constructed on surface-functionalized carbon nanotubes (CNTs) and demonstrated as a multifunctional electrocatalyst for both alkaline hydrogen and oxygen electrolysis. The exceptional catalytic activity and multifunctionality of the catalyst composites across all key reactions enable a regenerative fuel cell system to achieve high round-trip efficiency at industrial-level current densities.

Regenerative fuel cells hold significant potential for efficient, large-scale energy storage by reversibly converting electrical energy into hydrogen and vice versa, making them essential for leveraging intermittent renewable energy sources. However, their practical implementation is hindered by the unsatisfactory efficiency. Addressing this challenge requires the development of cost-effective electrocatalysts. In this study, a carbon nanotube (CNT)-supported RuNi composite with low Ru loading is developed as an efficient and stable catalyst for alkaline hydrogen and oxygen electrocatalysis, including hydrogen evolution, oxygen evolution, hydrogen oxidation, and oxygen reduction reaction. Furthermore, a regenerative fuel cell using this catalyst composite is assembled and evaluated under practical relevant conditions. As anticipated, the system exhibits outstanding performance in both the electrolyzer and fuel cell modes. Specifically, it achieves a low cell voltage of 1.64 V to achieve a current density of 1 A cm− 2 for the electrolyzer mode and delivers a high output voltage of 0.52 V at the same current density in fuel cell mode, resulting in a round-trip efficiency (RTE) of 31.6% without further optimization. The multifunctionality, high activity, and impressive RTE resulted by using the RuNi catalyst composites underscore its potential as a single catalyst for regenerative fuel cells.

Carbon-centered radicals derived from N-heterocyclic carbene, which exhibit hybrid local and charge transfer states, can inhibit the nonradiative channels and open the radiative channels, thereby achieving a record photoluminescence quantum yield with a nanosecond lifetime in green light-emitting carbon-centered radicals. This work may open new avenues for designing high-efficiency doublet emitters in the green range.

Organic luminescent radicals possess considerable potential for applications in organic light-emitting diodes (OLEDs)-based visible light communication owing to their intrinsic advantages of nanosecond emission lifetimes and spin-allowed radiative transitions. However, the inherently narrow energy bandgap and multiple nonradiative channels of organic radicals make it difficult to achieve efficient green and blue light-emitting, which is not conducive to applying visible light communication in diverse fields. In this study, a series of carbon-centered radicals derived from N-heterocyclic carbenes are designed and synthesized, some of which exhibiting hybrid local and charge-transfer (HLCT) states that resulting in efficient green emission. The results of photophysical characterizations and theoretical calculations demonstrate that the luminescence efficiency is closely related to their emission states. This relationship inhibits the nonradiative channels while simultaneously opening the radiative channels of organic radicals exhibiting HLCT states but not those with locally excited states. Intriguingly, a high photoluminescence quantum yield value of up to 70.1% at 534 nm is observed, which is the highest among green light-emitting carbon-centered radicals reported to date. Based on this exceptional result, an OLED device is fabricated and achieved an external quantum efficiency of 8.8%. These results demonstrate its potential application in electroluminescent devices.

This article describes the convergence of materials science and art through the creation of self-assembled block copolymer lamellar thin films with vivid iridescence. These films are applied as coatings on window panels for an architectural installation as well as transformed into porous, structurally colored ceramics. The work demonstrates the potential of nanoscale engineering in artistic and architectural contexts.

Art and materials innovation have always been intertwined, dating back to the earliest human creations. In modern times, however, the increasing specialization of materials science often restricts artists' access to cutting-edge materials. Here, the materials science aspects of an art-science collaboration between artist Kimsooja and the Wiesner Lab at Cornell University, are detailed. The project involves the development of a custom-made iridescent block copolymer coating by means of self-assembly, originally applied to transparent window panels of a façade for the ≈14 m tall art installation: A Needle Woman: Galaxy Is a Memory, Earth is a Souvenir by artist Kimsooja. After several exhibitions in the US and Europe, the installation is now part of the permanent museum collection at Yorkshire Sculpture Park in Wakefield, UK. Full characterization of the solution blade-cast coatings show shear aligned, standing up lamellar morphologies that behave as volume-phase gratings with periodicities between 300 and 400 nm. Coatings are also applied to foldable (origami) paper and converted into iridescent porous ceramic materials. It is hoped this work inspires and informs communities across materials science, the arts, and architecture.

A gas sensor capable of monitoring acetylene in situ in a fluidic medium with high sensitivity, selectivity, rapid response, and long stability is developed using carbon nanotube-embedded polyimide. The sensor, with a built-in carbon-nanotube-based heater, maintains the optimal temperature for maximum performance in transformer oil even under severe mechanical stress, ensuring commercial-standard durability.

This study presents an acetylene gas sensor capable of in situ monitoring transformer oils. This sensor utilizes carbon nanotubes (CNTs) embedded in polyimide (PI) synthesized by floating catalyst chemical vapor deposition. Unlike conventional sensors that target hydrocarbon gases dissolved in oil and measure the gas extracted from the oil, the proposed CNT-PI sensor detects gas within the oil in real time. The PI embedding technique effectively anchors and shields the CNT network against fluidic damage, ensuring stable sensing performance over 6 months, even under friction stress caused by oil convection. Decorating CNTs with gold nanoparticles further enhances the sensitivity and response of the sensor. The sensor achieves a high response (10.5% at 30 ppm) and fast response/recovery times (28 s/77 s), Furthermore, the sensor demonstrates good response (10.4% at 30 ppm) and moderate response/recovery times (444 s/670 s) in an oil medium, which qualifies for industrial applications. Additionally, a CNT-PI-based heater is integrated into the sensor as a multilayer component, maintaining an optimal operating temperature of 90 °C. The CNT-PI sensor demonstrates consistent gas-sensing performance even after 10,000 bending cycles and exhibits superior characteristics, indicating its compatibility with various forms of transformers.

Anode-Free All Solid-State Batteries

The scene is the Animas Mountains range on the planet Mars. The first explorer and a mechanical rover stand facing another freezing sunrise, wind howling as a dust storm gathers strength, the thin air humming with radiation, an unconcerned landscape where anything is permitted. Powering the life support system and the rover are anode-free solid-state batteries, charting a path that others will follow in due time. More details can be found in article number 2410948 by Yixian Wang, Vikalp Raj, David Mitlin, and co-workers.

Synthesis of Red-Emitting Quantum Dots

A large number of quantum dots can spring up in the magic hat after performing the magic of a smart core/shell structure design. In article number 2413978 by Zhao Chen, Yang Li, Wai-Yeung Wong, and co-workers a reliable and easily controllable approach is provided to prepare over 0.5-kilogram colloidal quantum dots (CQDs), which feature high fluorescence quantum yields of over 90%, and afford their light-emitting diodes with high efficiency, high brightness, and long operation stability.

Multiparameter Detection

In article number 2410946, Ningsheng Xu, Shaozhi Deng, and co-workers propose plasmon polariton atomic cavity (PPAC) to construct monolithic multifunctional detector. With a footprint one-tenth the incident wavelength, the detector offers benchmarking intensity-, frequency-, and polarization-sensitive detection, rapid response, and sub-diffraction spatial resolution, all operating at room temperature across 0.22 to 4.24 THz. The unique advantages of PPAC detector make it promising for high-resolution imaging and polarization-coded communication.

Interfacial Atomic Mechanisms

In article number 2414317, Huaze Zhu, Huashan Li, Wei Kong, and co-workers reveal the interfacial atomic mechanisms governing the epitaxial growth of single-crystalline molybdenum disulfide on sapphire substrates. Through high-resolution characterization and theoretical calculations, the critical role of interfacial composition in determining single-crystalline quality is elucidated. These findings provide new theoretical insights for the controlled growth of single-crystalline two-dimensional materials.

Low-Field Magnetoresistance

In article number 2415426 by Yanan Zhao, Zhixin Guo, Ming Liu, and co-workers a notable low-field magnetoresistance (1.2×103%, 0.1 T) in the layered (NdNiO3) n :NdO films at a high temperature range (≈90–240 K) is obtained. Such layered phases raise the tunneling barriers and magnetic fluctuations at high temperatures, where small ferromagnetic domains are embedded in the antiferromagnetic domains. The achievement of such notable LFMR at high temperatures would advance the magnetic devices.

Biomimetic Metamaterials

In article number 2416314 by Xiaoming Liu, Qiang Wang, and co-workers, a novel metamaterial design, metal-insulator-metal metamaterials with dual coupling gradient resonators, is proposed for broadband absorption. By transforming “resonance points” into “resonance bands” and perfect coupling of the two gradient resonators in nanoscale and microscale dimensions, the GR-MIMs with a thickness of only 200 nm demonstrates ultra-broadband high absorption across the ultraviolet, visible, near-infrared, and mid-infrared spectra.

Biomimicry

In article number 2413939, Ulrich B. Wiesner and co-workers describe a science-art collaboration culminating in a 14-meter-tall art installation with ultra large molar mass block copolymer-based structural color, mimicking the optical behavior of a Morpho butterfly wing. Routes to overcoming the challenges of scaling up block copolymer synthesis and reproducible film formation to the architectural scale are addressed. The approach to generating films with block copolymer-based structural color is then broadened to include iridescent hybrid materials as well as ceramics.

Herein, a reliable and easily controllable approach is provided to prepare over 0.5-kilogram colloidal quantum dots (CQDs), which feature high fluorescence quantum yields of over 90%, and afford their light-emitting diodes with high efficiency, high brightness, and long operation stability.

It is known that large-scale synthesis of emitters affords colloidal quantum dot (CQD) materials with a great opportunity toward the mass production of quantum dot light-emitting diodes (QLEDs) based commercial electronic products. Herein, an unprecedented example of scalable CQD (> 0.5 kilogram) is achieved by using a core/shell structure of CdZnSe/ZnSeS/CdZnS, in which CdZnSe, ZnSeS, and CdZnS alloys are used as the inner core, transition layer and outermost shell, respectively. It exhibits a high fluorescence quantum yield (>90%), a robust excited state, and a fast radiative transition rate. The investigation of morphology and surface state reveals the possible reasons for such excellent optical properties, which include uniform size distribution, no undesired byproducts, and high defect tolerance. The QLEDs exhibit a peak external quantum efficiency of over 21%, a high luminance of over 9.5×104 cd m−2, and a long lifetime of over 1.0×106 h, corresponding to the state-of-the-art performance among the QLEDs based on the large-scale synthesis of CQDs. Therefore, it is believed that an efficient and reliable strategy is provided toward the large-scale synthesis of CQDs, which can be used as emitters in the QLEDs-based commercial electronic devices and make the mass production of these products a reality.