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All‐solid‐state lithium metal batteries (ASSLBs) offer an alternative route to safe and high energy density power sources. Sulfur‐based cathodes with high theoretical specific capacity and low cost are crucial for advancing ASSLBs. However, the electronic insulation and sluggish kinetics of sulfide materials like Li2S severely limit battery performance. Herein, the strategy is proposed that a highly electronic conductive Li2S‐NbSe2 material enhances the electrochemical performance through bidirectional self‐activation. The chemical interaction between Li2S and NbSe2 induces NbSe2‐xSx and Li2Se derivatization, serving as the basis for activation. The carrier transport properties, chemical evolution and self‐activation mechanism of Li2S‐NbSe2 during the oxidation–reduction process are revealed. The chemical activation of NbSe2‐xSx is explored to accelerate the electrochemical processes by modifying the conductivity of sulfur species and the conversion pathways without insulating Li2S and S aggregation. Therefore, ASSLBs using Li2S‐NbSe2 as cathode active material achieve an electrode‐level energy density of 394 Wh kg−1 and a power density of 524 W kg−1 at 1 C (4.35 mA cm−2) and 25 °C. The capacity retention after 100 cycles at 0.5 C is ≈99.3% with almost no degradation. This work provides new options and insights for the rational design and development of chalcogenide cathode active materials for high‐performance ASSLBs. [ABSTRACT FROM AUTHOR]

Maintaining a consistently high current density growth rate in the hydrogen evolution reaction is highly challenging because the limited mass transfer rate at the electrode/electrolyte interface will make the adsorption reaction as the rate‐determining step associated with a low hydrogen coverage, exhibiting a Tafel slope >120 mV dec–1. Therefore, maximizing the current density range in which the desorption reaction is the rate‐determining step, can significantly reduce the overpotential. Herein, a surface sulfur decoration strategy is presented to modify the molybdenum carbide electrocatalyst and achieve coordinated adsorption/desorption kinetics, leading to a dominant Volmer–Heyrovsky mechanism across a wide range of current densities. Both experimental and theoretical results validate the surface charge redistribution induced by sulfur decoration, which subtly optimizes the Gibbs free energy of hydrogen adsorption and enhances the in‐plane polarization field. As a result, the as‐obtained surface sulfur‐decorated molybdenum carbide electrocatalyst exhibits coordinated adsorption/desorption kinetics and efficient hydrogen delivery, ultimately surpassing the commercial Pt/C electrocatalyst for high‐efficiency hydrogen evolution. [ABSTRACT FROM AUTHOR]

Li6PS5Cl (LPSC), a sulfide solid-state electrolyte with an argyrodite structure, is one of the ideal electrolyte materials for the construction of all-solid-state lithium-ion batteries.It has good development prospects because of its high ionic conductivity (>3×10-3 S·cm-1) and good stability to lithium. In this work, LPSC was prepared by the combination of high-energy ball milling and inert atmosphere solid-phase sintering, and powder X-ray diffraction, Raman spectra, and scanning electron microscopy were used to investigate the effects of the preparation process on the structure, composition, electrical properties, and ion conductivity of LPSC. The results show that the extended ball milling time is beneficial to the amorphization and subsequent sintering of the LPSC precursor powder. The increase of the sintering temperature will promote the physical purity and electrical conductivity of the prepared LPSC electrolyte, but the high sintering temperature will lead to the decomposition of LPSC. The LPSC prepared by 8 h ball milling and 500℃ sintering has the highest ion/electron conductivity ratio (2.091×105) at room temperature, with ionic conductivity up to 4.049×10-3 S·cm-1 and electronic conductivity only 1.936×10-8 S·cm-1. The 712 NCM/LPSC/In-Li all-solid-state battery prepared with this electrolyte has a first-turn discharge specific capacity of 151.3 mAh·g-1 at a charge/discharge ratio of 0.1 C, and has excellent cycling stability.

Realizing the graded bandgap in absorber layer is very essential for high efficient thin film solar cells. However, such bandgap modification in kesterite-structured Cu2ZnSnSe4 is normally realized via high temperature sulfurization process (above 500°C), which is not only difficult to control the sulfurization depth, but also introduces additional deep defects because of the decomposition of absorber layer at such high temperature. In this study, a low-temperature sulfurization process (150°C) is developed. Such process not only inhibits the decomposition of Cu2ZnSnSe4 films and controls the elemental distribution very well, but also increase the surface bandgap of the absorber layer and form a gradient energy bandgap. Also, the density of deep-level defects in the Cu2ZnSnSe4 layer is reduced. As a consequence, the open circuit voltage of the solar cell is improved by 60 mV. This study paves the way towards the high efficient kesterite solar cell and other solar cells. [ABSTRACT FROM AUTHOR]

Dimensional Stable Anode (DSA) is a promising candidate for the electrodeposition of nonferrous metals. However, the industrial applications of DSA are limited due to the propensity of Ti substrate to easily undergo passivation. Theoretically analyses shows that TiMn2 has better corrosion resistance in highly acidic and strongly polarized environments, making it an ideal middle‐layer for DSA anodes. To investigate the corrosion resistance of TiMn2, N‐doped TiMn2 (N‐TiMn2) is prepared by the high‐temperature nitriding method. The high charge transfer resistance (Rpo) of N‐TiMn2 reduces the electron transfer ability of its surface and improves the chemical stability. Scanning electron microscopy, X‐ray diffraction, and Raman spectroscopy show that Ti/N‐TiMn2 can better inhibit the oxidation of Ti during electrochemical corrosion while forming a more stable α‐MnO2 film. The Ti/N‐TiMn2/MnO2 anode is prepared, and the theoretical lifetime reaches 541.5 days in zinc electrodeposition simulation experiments. This middle layer provides a new idea for developing the oxygen evolution anode in the electrowinning of nonferrous metals. [ABSTRACT FROM AUTHOR]

The two‐step sequential deposition method exhibits favorable operability for processing perovskite films. Due to the growth of the perovskite films largely depends on the pre‐deposited PbI2 films, the porous and rough PbI2 films are expected to facilitate the penetration of the organic amine salts. However, in air conditions, the porous and rough PbI2 films also facilitate the penetration of the water molecules, thus leading to diminished crystallinity. Despite substantial efforts aimed at inhibiting the decomposition of perovskite films, the performance of air‐processed perovskite solar cells (PSCs) remains unsatisfactory. Herein, the study presents that the PbI2 films with high exposure of layered planes and vanished of non‐layered planes have more effective to resist water erosion and promote the crystallization process of perovskite films. An amphoteric Lewis acid‐base molecule (cephalothin, a type of antibiotic) is added in PbI2 precursor solution to induce this highly layer‐oriented PbI2 film. Consequently, the perovskite films can be processed under humidity condition and yield the champion PSC with an outstanding power conversion efficiency of 24.45%. In addition, the unencapsulated devices maintain 80% of their initial power conversion efficiency after 1000 h storage in air and exhibit high thermal stability after 100 cycles at 25–70 °C. [ABSTRACT FROM AUTHOR]