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Garnet-based solid-state lithium metal batteries (SSMLBs) are considered one of the candidates that could realise the future application of lithium metal anodes owing to their inherent safety, high energy density and wide operating temperature range. However, the poor wettability and high impedance of the garnet/Li-metal anode interface limit the practical application of SSMLBs. In this work, an SnCl2 layer was prepared on the surface of an Li6.5La3Zr1.5Ta0.5O12 (LLZTO) solid-state electrolyte via a convenient wet-chemistry method. Next, the Li–Sn/LiCl hybrid ionic/electronic conducting layer was in situ formed through the conversion reaction between molten Li and SnCl2. This hybrid conducting layer can significantly reduce interfacial impedance, ensure the close contact between Li and the garnet interface, and inhibit the growth of Li dendrites. As a result, interfacial impedance was reduced from 293.9 Ω to 9.4 Ω, and the critical current density (CCD) of LLZTO was increased from 0.5 mA cm−2 to 0.8 mA cm−2. Besides, the Li/Li symmetric cell could work stably over 6000 h at a current density of 0.2 mA cm−2 without the formation of dendritic Li and interfacial contact failure. Furthermore, the hybrid conductive layer enables the full cell assembled with LFP or NCM622 to show greatly improved long-term cycle stability and rate performance. This simple wet-chemistry strategy and the excellent electrochemical performances in this work demonstrate a potential strategy to develop high-performance garnet-based solid-state lithium metal batteries. [ABSTRACT FROM AUTHOR]

Understanding the mechanism underlying thermostabilization in naturally stable enzymes and enhancing the thermostability of unstable enzymes are crucial aspects in enzyme engineering. Despite the development of various engineering methods, there remains substantial scope for improvement. In this study, a novel concept termed as the "short board" theory is proposed, which conceptualizes proteins as barrels with each component representing a jagged board. Notably, optimizing modifications to the shortest board yields optimal enhancements in terms of thermostability performance. To validate this theory, α‐amylase, an industrial bulk enzyme with multiple domains, is employed as a model enzyme. The existence of "short boards" and their impact on thermostability modification are demonstrated at the domain, residue, and atomic levels through experimental confirmation using domain substitution. Furthermore, a novel thermostable design and prediction model called Zero‐Shot Hamiltonian (ZSH) is established and evaluated on α‐amylase. This coevolutionary approach based on thermostability and deep learning exhibits remarkable success exclusively when applied to enzymes with fixed short boards. The integration of the "short board" theory with the ZSH model presents an innovative tool for enhancing enzymatic thermostability. [ABSTRACT FROM AUTHOR]

Lignin-derived porous carbons have emerged as promising electrode materials for supercapacitors. However, the challenge remains in designing and controlling their structure to achieve ideal electrochemical performance due to the complex molecular structure of lignin and its intricate chemical reactions during the activation process. In this study, three porous carbons were synthesized from lignin by spray drying and chemical activation with varying KOH ratios. The specific surface area and structural order of the prepared porous carbon continued to increase with the increase of the KOH ratio. Thermogravimetric-mass spectrometry (TG-MS) was employed to track the molecular fragments generated during the pyrolysis of KOH-activated lignin, and the mechanism of the thermochemical conversion was investigated. During the thermochemical conversion of lignin, KOH facilitated the removal of H and CO, leading to the formation of not only more micropores and mesopores, but also more ordered carbon structures. The pore structure exhibited a greater impact than the carbon structure on the electrochemical performance of porous carbon. The optimized porous carbon exhibited a capacitance of 256 F g at a current density of 0.2 A g, making it an ideal electrode material for high-performance supercapacitors. [ABSTRACT FROM AUTHOR]

Developing catalysts for the high efficiency of CO2 utilization and conversion is a hot topic and has attracted significant interest. Using systematic density functional theory (DFT) calculations, the stability and catalytic performance of TM-N3-C catalysts are determined by the element of the metal site and influenced by the local environment around TM atoms during CO2RR, which is mainly attributed to tailoring the electronic structure of the active center and its coordinated atoms. The influence of inherent features of the catalyst on properties was clarified. It is worth noting that an intrinsic descriptor (Ψ) of activity and selectivity for CO2-to-CH4 was assembled by inherent characteristics of electrocatalysts, such as the number of valence electrons (V), electronegativity (χ), and Hirshfeld charges (Q); the elevation altitude (H) from TM center to N3-C substrate; average bond length (d) of the TM atom and the nearest neighbor atoms; and metal-coordinated number (N). The volcano-shaped physical curves were established between Ψ and the limiting potential, and three promising TM-N3-C (Ru-II, Rh-II, and Pd-II) with moderate VM, QM, d, and H, and larger χM are distributed close to the summit of the volcano curve. This study is meaningful for understanding the mechanism of electrocatalytic CO2 reduction and the design of efficient electrocatalysts for CO2RR. [ABSTRACT FROM AUTHOR]