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Transition metal sulfides (TMS) exhibit significant promise as non‐noble‐metal electrocatalysts for the oxygen evolution reaction (OER) in alkaline environments, notwithstanding their susceptibility to long‐term instability due to the gradual leaching of surface‐reconstructed sulfate ions (SO42−). In this study, a sulfate ion‐assisted strategy is proposed to stabilize the surface‐reconstructed SO42− of FeNiS2. The findings reveal that SO42− experiences considerable loss in KOH due to the infinite concentration gradient of SO42− on the surface. Conversely, in K2SO4/KOH, this strategy mitigates rapid leaching and preserves the predominant surface‐reconstructed SO42−, thereby enhancing stability in both accelerated degradation (5000 cycles) and long‐term (≥120 h) tests, with ≈95% current density retained. Furthermore, the optimal concentration of SO42− proves to be crucial, as supported by both experimental and theoretical results. This approach offers insights into bolstering the long‐term OER stability of TMS and similar compounds, thereby advancing the prospects for widespread application in electrocatalytic water splitting. [ABSTRACT FROM AUTHOR]

Lithium nitrate is an attractive lithium additive in the construction of high‐performance lithium metal anodes with a Li3N‐rich solid electrolyte interphase (SEI) layer. However, the eight‐electron transfer process induces high energy barriers between LiNO3 and Li3N. Herein, the inner Helmholtz plane is tuned on a Li deposition host to attain sluggish/rapid LiNO3 decomposition kinetics, resulting in different intermediate content distributions of Li species in the SEI. Notably, lithium oxynitride (LiNO) is identified as the decomposition intermediate, and experimental and simulation results confirm its role in obstructing LiNO3 decomposition. Moreover, the results reveal that the dipole–dipole interaction between LiNO and the polar V≡N bond can change the ionic/covalent character of the N═O bonds, considerably facilitating the energy transfer process of the N═O cleavage, and promoting a LiNO3 reduction to achieve a Li3N‐rich SEI. Consequently, when the electrolyte contains 0.37 m LiNO3, dendrite, and dead Li formation are suppressed effectively with the VN system, and an average Coulombic efficiency of 99.7% over 1000 cycles (1 mA cm−2, 1 mAh cm−2) can be attained. These results can promote the nitride oxidation break process and pave the way for fabricating high‐performance Li3N‐rich lithium metal batteries. [ABSTRACT FROM AUTHOR]

The simultaneous optimization of sluggish reaction kinetics and mass transfer in bifunctional oxygen electrocatalysts for air cathodes remains a great challenge. This study utilizes CoAl‐layered double hydroxide as a metal precursor to fabricate a bifunctional oxygen electrocatalyst, denoted as CoAlOXD‐Thin. This electrocatalyst features a specific core–shell structure of Co species, which grows on an aerophilic and conductive substrate composed of Al2O3 and carbon. It is successfully demonstrated that the thickness of Co@Co3O4 core–shell structure can be easily controlled by selecting different precursors and the combination of Co core and Co3O4 shell optimizes the adsorption strength of intermediates, leading to enhanced catalytic performance. Additionally, the Al species plays a dual role. It not only facilitates the mass transfer of oxygen species but also hinders the 2e− pathway of oxygen reduction reaction, leading to improved selectivity. Notably, the Zn–air batteries utilizing CoAlOXD‐Thin demonstrate an impressive peak power density of 216.2 mW cm−2, a high specific capacity of 800.8 mAh gZn−1, and excellent cycling stability and reversibility, surpassing those of the Pt/C + RuO2 catalyst. This study presents a novel approach to enhance air cathode performance by optimizing reaction kinetics and mass transfer through precursor design. [ABSTRACT FROM AUTHOR]

For wide and safe applications of Li metal batteries, the suppression of Li dendrite growth during cycling is the most crucial yet challenging topic. In this work, an artificial protective interlayer of GO‐BQ@LiTFSI (GBL) is designed to overcome this issue. The GBL interlayer is prepared by incorporating graphene‐oxide sheets with a liquid organic eutectic mixture of 1,4‐benzoquinone and bis (trifluoromethane) sulfonamide lithium salt. With the exceptional merits of these functional materials, the incorporation endows the GBL interlayer with rich lithiophilic active sites, good ionic conductivity, superior thermal stability and compatibility with the electrolyte, and the precursor supply stations for the formation of a compact and LiF‐rich solid‐electrolyte interface (SEI). Consequently, the GBL effectively promotes the uniform nucleation of Li at low over‐potentials and regulates the Li‐ion flux, leading to the formation of planar Li metal. After utilizing the GBL interlayer in the Li||Li symmetric cells, high electrochemical stability for 600 h is achieved at a current density of 3 mA cm−2 and a capacity of 3 mAh cm−2. Remarkably, this modification enables Li||LiFePO4 full cells with 1600 cycles at 1C and a high‐capacity retention of 95.23% with a cathode mass loading of ≈6 mg cm−2. [ABSTRACT FROM AUTHOR]

This work describes a series of investigations carried out on sets of pristine and auxetic (negative Poisson's ratio (NPR)) open‐cell polyurethane foams subjected to relative humidity (RH) conditioning ranging from 9% to 92% at room temperature. The foams have been produced using a uniaxially thermoforming process. Pristine and auxetic foams have then been subjected to quasi‐static compressive cyclic loading (with maximum strains of 10% and 80%, respectively), as well as vibration transmissibility tests with base accelerations up to 2.29 g. Increasing levels of RH do not seem to statistically affect the moduli and PRs of foams subjected to lower maximum strains, however, especially the auxetic foams at higher compressive deformations show a decrease in the stiffness with the increase of the RH. The vibration tests show an increasing trend of the dynamic modulus of the foams with the increase of the RH. The results indicate the complexity of the interaction between foam architecture and absorption/desorption mechanisms occurring inside these porous auxetic materials. [ABSTRACT FROM AUTHOR]

N‐coordinated Ni sites (NiNx) are effective catalysts for the electrochemical reduction of CO2 to CO. In most researches, modulating the coordination environment of Ni atoms is focused on to improve electrochemical CO2 reduction (ECR) performance. However, the influence of the carbon substrate's structure on the intrinsic activity of NiNx is seldom investigated. The highly curved surface of carbon nanotubes (CNT) may provide a unique curvature effect on NiNx. It is found that the Ni residues in CNT can be atomized to form NiNx sites on the surface of CNT (Ni‐N/CNT@covalent triazine framework [CTF]) through high‐temperature pyrolysis, using a soluble CTF nanosheet as N precursor. The π‐conjugated and ultrathin 2D structure of CTF enables closer interfacial contact between CTF and CNT, which avoids the formation of a thick carbon layer to maximize the curvature effect. Theoretical data reveal that the NiN3 configuration may act as a highly active ECR site, and the curvature effect from CNT can further tune the electronic structure of NiN3, thus improving the ECR kinetics. The Ni‐N/CNT@CTF‐based flow‐cell electrolyzer exhibits a jCO of 201 mA cm−2 at −0.9 V with a high FECO of 98%. [ABSTRACT FROM AUTHOR]

Aqueous zinc‐ion batteries (AZIBs), recognized for their safety and environmental friendliness, hold significant promise for large‐scale energy storage. However, the rapid capacity degradation resulting from the dissolution of active cathode materials hampers the advancement of AZIBs. Here, Ru0.2V2O5∙0.41H2O (RuVO) is synthesized with remarkable capacity retention (98.2% over 5000 cycles at 10 A g−1). The pre‐intercalation of Ru3+ enhances the stability of both intrinsic and cycling structures, elevating the Gibbs free energy and suppressing V‐dissolution thermodynamically. Additionally, Ru3+ intercalation modulates the potential energy surface of Zn2+ migration, leading to the dominance of Zn2+ in the insertion/extraction mechanism, thereby kinetically impeding the dissolution reaction. This study elucidates the dissolution thermodynamics and kinetics of V‐based cathodes through a combination of experiments, mechanism analyses, and density functional theory (DFT) calculations. [ABSTRACT FROM AUTHOR]

Immunotherapy is an efficient approach to clinical oncology. However, the immune privilege of the central nervous system (CNS) limits the application of immunotherapeutic strategies for brain cancers, especially glioblastoma (GBM). Tumor resistance to immune checkpoint inhibitors is a further challenge in immunotherapies. To overcome the immunological tolerance of brain tumors, a novel multifunctional nanoparticle (NP) for highly efficient synergetic immunotherapy is reported. The NP contains an anti‐PDL1 antibody (aPDL1), upconverting NPs, and the photosensitizer 5‐ALA; the surface of the NP is conjugated with the B1R kinin ligand to facilitate transport across the blood‐tumor‐barrier. Upon irradiation with a 980 nm laser, 5‐ALA is transformed into protoporphyrin IX, generating reactive oxygen species. Photodynamic therapy (PDT) further promotes intratumoral infiltration of cytotoxic T lymphocytes and sensitizes tumors to PDL1 blockade therapy. It is demonstrated that combining PDT and aPDL1 can effectively suppress GBM growth in mouse models. The proposed NPs provide a novel and effective strategy for boosting anti‐GBM photoimmunotherapy. [ABSTRACT FROM AUTHOR]

Metal‐organic frameworks with high surface areas are currently being widely used for in‐depth studies on hydrogen storage with the aim of discussing the difficulties created by environmental degradation caused by the burning of fossil fuels. Understanding the effect of varied metal ion doping on adsorption position and energy is crucial to understanding the adsorption process. The adsorption behavior of NU‐1501‐Al and NU‐1501‐Fe was investigated using a combination of Grand Canonical Monte Carlo and Density Functional Theory in this study. The calculations reveal that aluminum has a larger charge than iron and higher adsorption energy. As the loading increases, hydrogen is primarily adsorbed by metal atoms and the carbon atoms of the metal‐benzene ring are connected to metal‐oxygen atoms. The research hopes to provide molecular‐level insights into the adsorption behavior of porous materials doped with different metals, which could be used to screen materials that improve gas adsorption, separation, and other expansion characteristics. [ABSTRACT FROM AUTHOR]

A unique strategy is reported to constrain the nucleation centers for multilayer graphene (MLG) and, later, single-crystal graphene domains by gettering carbon source on backside of the flat Cu foil, during chemical vapor deposition. Hitherto, for a flat Cu foil, the top-surface-based growth mechanism is emphasized, while overlooking the graphene on the backside. However, the systematic experimental findings indicate a strong correlation between the backside graphene and the nucleation centers on the top-surface, governed by the carbon diffusion through the bulk Cu. This understanding steers to devise a strategy to mitigate the carbon diffusion to the top-surface by using a carbon 'getter' substrate, such as nickel, on the backside of the Cu foil. Depth profiling of the nickel substrate, along with the density functional theory calculations, verifies the gettering role of the nickel support. The implementation of the backside carbon gettering approach on single-crystal graphene growth results in lowering the nucleation density by two orders of magnitude. This enables the single-crystal domains to grow by 6 mm laterally on the untreated Cu foil. Finally, the growth of large-area polycrystalline single layer graphene, free of unwanted MLG domains, with significantly improved field-effect mobility of ≈6800 cm2 V−1 s−1 is demonstrated. [ABSTRACT FROM AUTHOR]