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DNA-Encoded Chemical Libraries - A BIOLOGICAL RIG SEMINAR

The discovery of small organic ligands, capable of specific recognition of protein targets of interest, is a central problem in Chemistry, Pharmacy, Biology and Medicine. Traditionally, small organic ligands to proteins are discovered by screening, one by one, individual compounds from chemical libraries. However, the technology is cumbersome, very expensive and is typically limited to the testing of up to one million compounds. DNA -encoded chemical library (DEL) technology allows the construction and screening of much larger compound libraries, without the need for expensive instrumentations and logistics. DELs are collections of molecules, individually coupled to distinctive DNA fragments, serving as amplifiable identification barcodes. Binding compounds can be selected using affinity capture procedures, with the protein target of interest immobilised on magnetic beads. After this “fishing” experiment, the DNA barcodes can be PCR amplified and quantified using high-throughput DNA sequencing [1]. In this lecture, I will present theory and applications of DEL technology. I will also show examples of DEL -derived ligands, isolated in our laboratories, which have been tested in patients with cancer, with promising clinical results.

• Speaker: Professor Dario Neri - CEO and CSO of Philogen, Professor of ETH Zürich, Honorary Senior Visiting Fellow, Department of Radiology, University of Cambridge (UK)
• Monday 31 March 2025, 15:00-16:00
• Venue: Department of Chemistry, Cambridge, Pfizer LT.
• Series: Biological Chemistry Research Interest Group; organiser: Xani Thorman.

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Recent aspects of chaperone functions in health and disease - A BIOLOGICAL RIG SEMINAR

Abstract not available

• Speaker: Prof. Ulrich Hartl - Max-Planck-Institute of Biochemistry
• Tuesday 08 April 2025, 13:30-14:30
• Venue: Department of Chemistry, Cambridge, Pfizer LT.
• Series: Biological Chemistry Research Interest Group; organiser: Xani Thorman.

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Joint ChemBio and Synthesis RIG Seminar - Chemical Biology Tools for Measuring Drug Delivery

Large-molecule therapeutics including peptides, oligonucleotides, and proteins make up a large and growing portion of the drug development pipeline. One of the greatest barriers to developing these drugs is cell penetration. Most enter the cell through a complex pathway involving endocytosis followed by endosomal escape. This process is so poorly understood and difficult to study that it is challenging simply to measure how much compound has actually accessed the cytosol at any given point. The Kritzer Lab has developed new tools for making these and related measurements. The Chloroalkane Penetration Assay (CAPA) is a versatile assay that measures cell penetration using cellularly expressed HaloTag protein and a small chloroalkane tag on the molecule-of-interest. CAPA has been used by the Kritzer group to measure cell penetration for many classes of peptide and oligonucleotide therapeutics, to measure penetration to different subcellular compartments, and to measure relative penetration in different cell types. CAPA has also been adopted by academic and industrial groups all over the world to investigate cell penetration. The Kritzer group has also used molecular evolution to produce new HaloTag variants which work optimally with a fluorogenic benzothiadiazole dye. The resulting “BenzoTag” system allows for turn-on, no-wash cell labeling in seconds. BenzoTag is currently being applied to produce a “turn-on” version of CAPA for continued investigation of drug delivery and mechanisms of endosomal escape

• Speaker: Joshua Kritzer (Tufts University)
• Friday 23 May 2025, 14:00-15:00
• Venue: Dept. of Chemistry, Wolfson Lecture Theatre.
• Series: Synthetic Chemistry Research Interest Group; organiser: Jasmine Mitchell.

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The Druggable Transcriptome Project: From Chemical Probes to Precision Medicines

A scientific challenge is to understand biological pathways and to exploit the targets within them for therapeutic development. Coding and non-coding RNAs both directly cause disease, whether by mutation or aberrant expression. Akin to proteins, RNA structure often dictates its function in health or dysfunction in disease. RNA , however, is generally not considered a target for small molecule chemical probes and lead medicines, despite its immense potential. The focus of our research program is to uncover fundamental principles that govern the molecular recognition of RNA structures by small molecules to enable design of chemical probes that targeting disease relevant RNA structures to perturb and study their function.

I will describe using evolutionary principles to identify molecular recognition patterns between small molecules and RNA structures by studying the binding of RNA fold libraries to small molecule libraries. These interactions are computationally mined across the human transcriptome to define cellular RNAs with targetable structure. Such an approach has afforded bioactive interactions that have uncovered new biology, where the small molecules bind to functional structures within a target RNA . We have devised a strategy to imbue biologically silent RNA -small molecule interactions with cellular activity. Chimeras comprising an inactive small molecule and ribonuclease recruiter trigger targeted degradation of disease-causing RNAs. These degraders affect the biology of RNA in specific ways in cells and in mouse models of various diseases and can rationally reprogram protein-targeted medicines for RNA . Lastly, we have recently devised unbiased transcriptome wide approaches to define the RNA bound by small molecules is live cells. This allows us to study the RNA targets that are bound by small molecules, the selectivity of these interactions, and ways in which compounds of various types can modulate disease biology.

• Speaker: Matthew Disney - Scripps Research Institute
• Tuesday 01 April 2025, 14:30-15:30
• Venue: Department of Chemistry, Cambridge, Pfizer lecture theatre.
• Series: Biological Chemistry Research Interest Group; organiser: Xani Thorman.

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A versatile assembly method is developed to uniformly assemble 2D single-crystal copper nanosheets (Cu NS) onto substrates with complex shapes via ultrasonication process. This technique leverages cavitation effects to deposit monolayer Cu NS films with minimal overlap. The assembly is optimized by tuning solvent polarity and substrate surface energy. Demonstrated applications include a resistive heater, highlighting the potential in flexible electronics.

Abstract

Scalable and cost-effective fabrication of conductive films on substrates with complex geometries is crucial for industrial applications in electronics. Herein, an ultrasonic-driven omni-directional and selective assembly technique is introduced for the uniform deposition of 2D single-crystalline copper nanosheets (Cu NS) onto various substrates. This method leverages cavitation-induced forces to propel Cu NS onto hydrophilic surfaces, enabling the formation of monolayer films with largely monolayer films with some degree of nanosheet overlap. The assembly process is influenced by solvent polarity, nanosheet concentration, and ultrasonic parameters, with non-polar solvents significantly enhancing Cu NS adsorption onto hydrophilic substrates. Furthermore, selective assembly is achieved by patterning hydrophobic and hydrophilic regions on the substrate, ensuring precise localization of Cu NS films. The practical potential of this approach is demonstrated by fabricating a Cu NS-coated capillary tube heater, which exhibits excellent heating performance at low operating voltages. This ultrasonic-driven and selective assembly method offers a scalable and versatile solution for producing conductive films with tailored geometries, unlocking new possibilities for applications in flexible electronics, energy storage, and wearable devices with complex structural requirements.

This study introduce a novel approach to enhancing cathode-SPE compatibility by utilizing the same poly(ionic liquid) (PolyIL)-based material in both the SPE and the cathode binder. A modified biomass-based PolyIL substrate, enriched with highly negatively charged C═O and ─OH groups, is incorporated into the SPE to improve Li+ migration and strengthen its mechanical properties. The Li||LiFePO₄ cell, assembled via in situ photopolymerization, demonstrate stable cycling for over 1100 cycles, while the Li||NCM811 cell operated reliably at a high cut-off voltage of 4.8 V for 100 cycles.

Abstract

Lithium metal batteries (LMBs) with solid polymer electrolytes (SPEs) offer higher energy density and enhance safety compared to the Li-ion batteries that use a graphite anode and organic electrolytes. However, achieving long cycle life for LMBs while enabling the use of high-voltage cathodes required the compatibility between cathode-SPE, rather than focusing solely on the individual components. This study presente a dual-functional poly(ionic liquid) (PolyIL)-based material that simultaneously serves as an SPE matrix and a cathode binder, constructing a cathode-SPE interface with exceptional (electro)chemical compatibility owing to the high ionic conductivity and wide electrochemical stability window. Additionally, a modified cellulose acetate (CA)-based PolyIL substrate, enriched with C═O and ─OH groups, is designed rationally and incorporated to assist the Li+ migration, leveraging their highly negative charge, and enhancing the mechanical strength of the SPE. Furthermore, an in situ polymerization approach is employed to assemble the cells, improving the physical compatibility at the cathode-SPE interface. As a result, the Li||LFP cell demonstrate stable cycling beyond 1100 cycles, and the Li||NCM811 cell reliably operates at a high cut-off voltage of up to 4.8 V.

Synthesis of topological semimetal TaAs2 nanowires in situ encapsulated with a thin SiO2 shell unravel a richness of intertwined topological phases manifested by their magnetotransport features: A near-room-temperature metal-to-insulator transition, strong expressions of topologically nontrivial surface transport, giant magnetoresistance with direction-dependent sign reversal, chiral anomaly, and a unique double pattern of Aharonov–Bohm oscillations.

Abstract

Nanowires (NWs) of topological materials are emerging as an exciting platform to probe and engineer new quantum phenomena that are hard to access in bulk phase. Their quasi-1D geometry and large surface-to-bulk ratio unlock new expressions of topology and highlight surface states. TaAs2, a compensated semimetal, is a topologically rich material harboring nodal-line, weak topological insulator (WTI), C2-protected topological crystalline insulator, and Zeeman field-induced Weyl semimetal phases. We report the synthesis of TaAs2 NWs in situ encapsulated in a dielectric SiO2 shell, which enable to probe rich magnetotransport phenomena, including metal-to-insulator transition and strong signatures of topologically nontrivial transport at remarkably high temperatures, direction-dependent giant positive, and negative magnetoresistance, and a double pattern of Aharonov–Bohm oscillations, demonstrating coherent surface transport consistent with the two Dirac cones of a WTI surface. The SiO2-encapsulated TaAs2 NWs show room-temperature conductivity up to 15 times higher than bulk TaAs2. The coexistence and susceptibility of topological phases to external stimuli have potential applications in spintronics and nanoscale quantum technology.

Big Picture Talk: Bhopal 40 years on - What have we learned?

Our departmental seminar series, Bigger Picture Talks, runs throughout the academic year, inviting thought-leaders from across the world driving significant advances in our impact areas of energy, health and sustainability to share and discuss their work with us.

This talk will hear from alumni Professor Fiona Macleod, Professor of Process Safety at the University of Sheffield, who will talk about safety in the chemical engineering industry, using the worst disaster in history as a lens for why safety matters.

On the night of 2 and 3 December 1984 a toxic gas release from the Union Carbide pesticide factory in Bhopal, India caused thousands of deaths and hundreds of thousands of life-changing injuries. Forty years later, the rusting factory equipment still towers above buried hazardous waste in the abandoned factory. I visited the site of the former Union Carbide site in Bhopal India to try to understand what went so horribly wrong.

1. What caused the worst accident in the history of the chemical industry? 2. Why was the accident never properly investigated? 3. What can we learn about process safety from revisiting the accident? 4. Why has no clean-up been undertaken in 40 years?

• Speaker: Professor Fiona Macleod
• Tuesday 06 May 2025, 14:30-15:15
• Venue: Lecture Theatre 1, Department of Chemical Engineering and Biotechnology, West Cambridge Site.
• Series: Chemical Engineering and Biotechnology; organiser: ejm94.

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Ocean dynamics in the Ross Ice Shelf cavity from in situ observations

The future response of ice shelves to climate through ocean warming is a key unknown for climate projections, especially global sea level rise. The Ross Ice Shelf ocean cavity is one of the least observed regions in the ocean, with its broad circulation patterns primarily inferred from remotely sensed estimates of tides, bathymetry, and melt rates. I aim to advance our understanding of the ocean cavity under the Ross Ice Shelf – the southern-most and largest-by area of all Earth’s ice shelves. To achieve this, I analyzed a multi-year hydrographic moored timeseries from the central Ross Ice Shelf cavity (80◦39.497′S, 174◦27.678′E). These data help address three key processes: (i) the general circulation; (ii) the appearance and impact of baroclinic eddy events; and (iii) tidal modulation of the ice-ocean boundary layer structure and the implications for ice melting. In terms of circulation and the inter-annual changes, stronger melting/refreezing occurred between late September 2019 to late December 2019, which is linked to the inter-annual sea ice production in the Ross Ice Shelf Polynya. Notably, cold-water interleaving in the mid-water column exhibits distinct seasonality. An analysis of baroclinic eddies identifies coherent structures that are around 22 km in diameter with a velocity scale of between 0.8 and 1.8 cm/s. The thermohaline structure of the eddies suggests that they have the potential to entrain High Salinity Shelf Water from the benthic water column to the mid-water column. On the question of tidal modulation of the ice shelf-ocean interaction, the results suggest that tides modulate the melt rate by altering the boundary layer structure over a spring-neap cycle. These new findings demonstrate the rich variability within the Ross Ice Shelf ocean cavity, ranging from large interannual-seasonal scales, through to multi-week eddy scales and then down to tidal and mixing timescales.

• Speaker: Yingpu Xiahou, University of Auckland
• Wednesday 23 April 2025, 14:00-15:00
• Venue: BAS Seminar Room 330b.
• Series: British Antarctic Survey - Polar Oceans seminar series; organiser: Dr Birgit Rogalla.

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A thermo-electrochemically compatible polymer electrolyte is proposed with a locally conjugated structure through self-regulation of paired tertiary anilines coupled with in situ polymerization, which significantly reconstructs an improved Li+ solvation and enhances electrode/electrolyte interfacial stability of LMBs. This concept provides an important theoretical basis and technical means for achieving practical high energy/power density LMBs.

Abstract

Pursuing high energy/power density lithium metal batteries (LMBs) with good safety and lifespan is essential for developing next-generation energy-storage devices. Nevertheless, the uncontrollable degradation of the electrolyte and the subsequent formation of inferior electrolyte/electrode interfaces present formidable challenges to this endeavor, especially when paring with transition metal oxide cathode. Herein, a fireproof polymeric matrix with a local conjugated structure is constructed by 4,4′-methylenebis (N, N-diglycidylaniline) (NDA) monomer via in situ polymerization, which promotes the use of ester-based liquid electrolyte for highly stable LMBs. The conjugated tertiary anilines in this PNDA electrolyte effectively tune the Li+ solvation sheath and generate conformal protective layers on the electrode surfaces, resulting in excellent compatibility with both high-voltage cathodes and Li-metal anodes. Moreover, the accumulated electron density endows PNDA with a powerful capability to seize and eliminate the corrosive hydrofluoric acid, which strikingly mitigates the irreversible structure transformation of LiNi0.8Mn0.1Co0.1O2 (NMC) particles. As a result, the PNDA-based Li||LiFePO4 and Li||NMC cells reach excellent electrochemical and safety performance. This study provides a promising strategy for the macromolecular design of electrolytes and emphasizes the importance of “local conjugation” within the polymers for LMBs.

An efficient and safe circular-RNA delivery system circSCMH1@LNP1 is developed for direct nose-to-brain delivery of circRNA SCMH1 to ischemic lesions. Experiments demonstrate that intranasally administrated circSCMH1@LNP1 significantly accumulates in the peri-infarct region of PT stroke mice, thereby improving functional recovery by enhancing synaptic plasticity, vascular repair, neuroinflammation relief, and myelin sheath formation.

Abstract

Ischemic stroke represents one of the leading cerebrovascular diseases with a high rate of mortality and disability globally. To date, there are no effective clinical drugs available to improve long-term outcomes for post-stroke patients. A novel nucleic acid agent circSCMH1 which can promote sensorimotor function recovery in rodent and nonhuman primate animal stroke models has been found. However, there are still delivery challenges to overcome for its clinical implementation. Besides, its effects on post-stroke cognitive functions remain unexplored. Herein, lipid nanoparticle circSCMH1@LNP1 is established to deliver circSCMH1 and explore its therapeutic efficacy comprehensively. Distribution experiments demonstrate that intranasal administration of circSCMH1@LNP1 significantly increases circSCMH1 distribution in the peri-infarct region and reduces its non-specific accumulation in other organs compared to intravenous injection. Therapeutic results indicate that circSCMH1@LNP1 promotes synaptic plasticity, vascular repair, neuroinflammation relief, and myelin sheath formation, thereby achieving enhanced sensorimotor and cognitive function recovery in post-stroke mice. In conclusion, this research presents a simple and effective LNP system for efficient delivery of circSCMH1 via intranasal administration to repair post-stroke brain injury. It is envisioned that this study may bridge a crucial gap between basic research and translational application, paving the way for clinical implementation of novel circSCMH1 in post-stroke patient management.

Super-hard wood-based composites (WBC) are designed and developed inspired by the mesoscale homogeneous lignification process intrinsic to tree growth. This innovative hybrid structure is achieved by leveraging the infusion of low-molecular-weight phenol formaldehyde resin into the cell walls of thin wood slices, followed by a unique multi-layer construction and high-temperature compression.

Abstract

The growing demand for high-strength, durable materials capable of enduring extreme environments presents a significant challenge, particularly in balancing performance with sustainability. Conventional materials such as alloys and ceramics are nonrenewable, expensive, and require energy-intensive production processes. Here, super-hard wood-based composites (WBC) inspired by the meso-scale homogeneous lignification process intrinsic to tree growth are designed and developed. This hybrid structure is achieved innovatively by leveraging the infusion of low-molecular-weight phenol formaldehyde resin into the cell walls of thin wood slices, followed by a unique multi-layer construction and high-temperature compression. The resulting composite exhibits remarkable properties, including a Janka hardness of 24 382 N and a Brinell hardness of 40.7 HB, along with exceptional antipiercing performance. The created super-hard, sustainable materials address the limitations of nonrenewable resources while providing enhanced protection, structural stability, and exceptional resilience. The WBC approach aligns with UN Sustainable Development Goals (SDGs) by offering extra values for improving personal safety and building integrity across various engineering applications.

A tailor-made blue organic emitter with hot exciton and aggregation-induced emission characteristics serves as a sensitizer in the innovative sensitizing system with a dual-channel stepwise energy transfer feature. The established material and device approach enables efficient, stable blue organic light-emitting diodes with narrow emission and low-efficiency roll-off at high luminance.

Abstract

Marching toward next-generation ultrahigh-definition and high-resolution displays, the development of high-performance blue organic light-emitting diodes (OLEDs) with narrow emission and high luminance is essential and requires conceptual advancements in both molecular and device design. Herein, a blue organic emitter is reported that exhibits hot-exciton and aggregation-induced emission characteristics, and use it as a sensitizer in the proposed triplet–triplet annihilation (TTA)-assisted hot-exciton-sensitized fluorescence (HSF) device, abbreviated THSF. Results show that through dual-channel stepwise Förster and Dexter energy transfer processes, the THSF system can simultaneously enhance exciton utilization, accelerate exciton dynamics, and reduce the concentration of triplet excitons. The smooth management of excitons makes the overall performance of the THSF device superior to the control TTA fluorescence and HSF devices. Furthermore, a high-performance narrowband blue (CIEx,y = 0.13, 0.12) OLED is achieved using a two-unit tandem device design, providing an excellent maximum external quantum efficiency of 18.3%, a record-high L 90% (the luminance where the ƞ ext drops to 90% of its peak value) of ≈20 000 cd m−2, and a long half-lifetime at 100 cd m−2 initial luminance of ≈13 256 h. These results showcase the great potential of the THSF strategy in realizing efficient and stable blue OLEDs with narrow emission and high luminance.

This work developed a LiC6@Li counter electrode, as an alternative to Li metal for more precisely evaluating the electrochemical behavior of electrode materials at low temperatures. The low interfacial resistances facilitate preferential de-intercalation of Li+ from LiC6, resulting in a sharp decreased over-potential at low temperatures. Meanwhile, the rapid replenishment of Li+ through the solid–solid-connection reaction maintains stable LiC6@Li potential.

Abstract

Li metal, as a counter electrode, is widely used for electrode materials evaluation in coin type half-cells. However, whether this configuration is suitable for different working conditions has often been neglected. Herein, the large resistance and high cathodic/anodic over-potential of Li metal at low temperature are highlighted, revealing its incompetence as counter electrode on cryogenic condition. In view of this, a novel LiC6@Li composite electrode is developed as a promising substitution for electrode materials evaluation. In the LiC6@Li electrode, Li+ de-intercalated from LiC6 preferentially due to the low interface resistance of LiC6, presenting a cathodic/anodic over-potential of 0.05 V (67 µA cm−2) at −20 °C, which is ten times lower than that of Li metal. Moreover, the rapid lithium replenishment into LiC6 from Li metal enables a stable potential of LiC6@Li. Consequently, the LiC6@Li-based half-cells enabled more precise evaluation of the Li+ storage potential and specific capacities of a series of electrode materials at low temperature. As an extension, KC8@K is also successfully prepared as a superior counter electrode to K metal. This work proposes a suitable counter electrode for more accurately evaluating electrode materials at subfreezing scenarios, demonstrating the necessity of specialized electrode evaluation systems for particular operating conditions.

The fabricated oriented chitosan nanofibrillar hydrogels (O-CN gels), via the synergy strategy of protein templating and mechanical training, achieve cartilage-like structure and mechanical performances, as well as high-water retention similar to cartilage. The resulting O-CN gels has excellent prospects in load-bearing cartilage engineering application.

Abstract

Cartilage, as a load-bearing tissue with high-water content, exhibits excellent elasticity and high strength. However, it is still a grand challenge to develop cartilage-adaptive biomaterials for replacement or regeneration of damaged cartilage tissue. Herein, protein templating and mechanical training is integrated to fabricate crystal-mediated oriented chitosan nanofibrillar hydrogels (O-CN gels) with similar mechanical properties and water content of cartilage. The O-CN gels with an ≈74 wt% water content exhibit high tensile strength (≈15.4 MPa) and Young's modulus (≈24.1 MPa), as well as excellent biocompatibility, antiswelling properties, and antibacterial capabilities. When implanted in the box defect of rat's tails, the O-CN gels seal the cartilage (annulus fibrosus) defect, maintain the intervertebral disc height and finally prevent the nucleus herniation. This synergy strategy of protein templating and mechanical training opens up a new possibility to design highly mechanical hydrogels, especially for the replacement and regeneration of load-bearing tissues.

A novel composite proton exchange membrane (PEM) design that leverages carboxylic acid-functionalized polymers of intrinsic microporosity (cPIM-1) and polyvinylpyrrolidone (PVP). Harnessing Lewis acid-base interactions enables the development of a synergistic microporous structure that confines phosphoric acid clusters, enhancing proton conductivity and durability. This work addresses critical challenges in PEM development, while proposing a solutionfor the design of next-generation membranes.

Abstract

High-temperature proton exchange membrane fuel cells (HT-PEMFCs) is regarded as a promising energy conversion system owing to simplified water management and enhanced tolerance to fuel impurities. However, phosphoric acid (PA) leaching remains a critical issue, diminishing energy density and durability, posing significant obstacle to the commercial development of HT-PEMFCs. To address this, composite membranes incorporating the carboxylic acid-modified polymer of intrinsic microporosity (cPIM-1) are designed as framework polymer, blended with polyvinylpyrrolidone (PVP) for HT-PEMFCs. The Lewis acid-base interactions between cPIM-1 and PVP created an extensive hydrogen-bonding network, improving membrane compatibility. The optimized microporous structure and multiple anchoring sites gave rise to “domain-limited” PA clusters, enhancing the capillary effect. Simultaneously, improved hydrophobicity synergistically optimizes catalytic interface, promoting continuous and stable proton transfer. The HT-PEMFCs based on PVP/cPIM-1 composite membrane achieved a peak power density of 1090.0 mW cm−2 at 160 °C, representing a 152% improvement compared to PVP/PES membrane. Additionally, it demonstrated excellent durability, with a voltage decay of 0.058 mV h−1 over 210 h of accelerated stress test corresponds to more than 5000 h of constant current density durability test. This study presents a promising strategy for the development of high-performance and durable novel membranes in various energy conversion systems.

Energy Environ. Sci., 2025, Accepted Manuscript
DOI: 10.1039/D4EE05689B, PaperZhongbin Pan, Yu Cheng, Zhicheng Li, Pang Xi, Peng Wang, Xu Fan, Hanxi Chen, Jinjun Liu, Junfei Luo, Jinhong Yu, Minhao Yang, Jiwei Zhai, Weiping Li
Electrostatic capacitors are typically necessary to operate in harsh-temperature environments to fulfill the demanding requirements of renewable energy, electrified transportations, and advanced propulsion systems. However, achieving exceptional capacitive performance in...
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Arylboronic acids are explored for use in the electrolyte engineering of Li─S batteries. The theoretically and experimentally verified coordination and mediation chemistry of arylboronic acids can not only stabilize the anode interface but also accelerate the sluggish sulfur conversion. 3,5-bis(trifluoromethyl)phenylboronic acid (BPBA) is chosen as a suitable electrolyte modifier, significantly improving the electrochemical performance of Li─S batteries.

Abstract

Lithium-sulfur (Li─S) batteries offer a promising avenue for the next generation of energy-dense batteries. However, it is quite challenging to realize practical Li─S batteries under limited electrolytes and high sulfur loading, which may exacerbate problems of interface deterioration and low sulfur utilization. Herein, the coordination and mediation chemistry of arylboronic acids that enable energy-dense and long-term-cycling Li─S batteries is proposed. The coordination chemistry between NO3 − and arylboronic acids breaks the resonance configuration of NO3 − and thermodynamically promotes its reduction on the anode, contributing to a mechanically robust interface. The mediation chemistry between lithium arylborate and polysulfides distorts S─S/Li─S bonds, alters the rate-determining step from Li2S4→Li2S2 to Li2S6→Li2S4, and homogeneously accelerates the sulfur redox kinetics. Li─S batteries using 3,5-bis(trifluoromethyl)phenylboronic acid (BPBA) show excellent cycling stability (1000 cycles with a low capacity decay rate of 0.033% per cycle) and a high energy density of 422 Wh kg−1 under aggressive chemical environments (high sulfur loading of 17.4 mg cm−2 and lean electrolyte operation of 3.6 mL gS −1). The basic mechanism of coordination and mediation chemistry can be extended to other arylboronic acids with different configurations and compositions, thus broadening the application prospect of arylboronic acids in the electrolyte engineering of Li─S batteries.

Sub-nanowires organohydrogels featuring a dual-phase structure are fabricated through the simple mixing of hydroxyapatite sub-nanowires with organic solvent and aqueous phase, directly forming a stable water-in-oil structure. The organohydrogels inherently possess rapid self-healing ability, exhibit specific temperature-responsive behavior, and are broadly compatible with a variety of organic solvents and polymers.

Abstract

Organohydrogels have significant applications in numerous fields. The current synthetic strategies generally rely on the intricate and complex design of lipophilic or hydrophilic polymers to achieve the goal of oil-water interpenetration. Herein, sub-nanowires organohydrogels with a dual-phase structure are fabricated by simply mixing hydroxyapatite sub-nanowires with organic solvent and aqueous phase. The sub-nanowires in the oil phase provide structural support, while surfactants in the sub-nanowires exist at the interface between oil and water, thus forming the water-in-oil structure. The organohydrogels possess commendable mechanical properties, an inherent self-healing ability, and a specific temperature-responsive behavior. Moreover, the organohydrogels are compatible with a variety of organic solvents and polymers, reserving the promise for wide-range applications in the future.

Interventions and Counterfactuals for the Working Programmer

Correlation famously does not imply causation! But how then can we answer interventional questions such as “Does smoking cause cancer?” or even counterfactual ones as “If I had left one minute earlier, would I have managed to arrive on time?” This is the subject of Causal Inference, as pioneered and formalized by Judea Pearl. In my talk, I want to focus on how such problems can be modelled and solved using tools from programming languages theory.

I will aim to give a general introduction to causal inference from a programmer’s point of view. I will then present work-in-progress from an ongoing collaboration dedicated to the extension of a probabilistic programming language to a causal probabilistic programming language; this includes operational semantics, a type system and denotational semantics using graded monads.

• Speaker: Dario Stein (Radboud University)
• Friday 28 March 2025, 14:00-15:00
• Venue: SS03, Computer Laboratory.
• Series: Logic and Semantics Seminar (Computer Laboratory); organiser: Ioannis Markakis.

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