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For the development of electrolyte additives as an effective strategy to improve the performance of zinc‐ion batteries (ZIBs), most researchers focus on the functional groups but overlook the crucial molecular configuration. Herein, six stereoisomers of 2,3,4,5‐tetrahydroxyvaleraldehyde with identical groups but various spatial arrangements are studied as the electrolyte additive in ZIBs. Based on the experimental analysis and theoretical calculations, the adsorption with Zn (002) plane is found to be an important dominant for the stereoisomer to enhance the Zn anode performance. Among these stereoisomers, D‐Arabinose with preferential and strongest chemisorption effect modifies the anode/electrolyte interface most effectively, leading to the highest stability and reversibility of the Zn anode. The adsorbed D‐Arabinose shows multifunctional effects at the interface, which not only regulates the Zn2+ solvation structure and reconfigures the hydrogen bond framework, but also facilitates uniform Zn2+ deposition by promoting 3D Zn2+ diffusion and homogenizing the electric field. Therefore, with the D‐Arabinose additive in ZnSO4 electrolyte, the undesired Zn dendrite growth and side reactions including hydrogen evolution reaction, corrosion, and passivation are significantly limited during the Zn plating/stripping processes. This work proposes a new insight toward the optimal molecular configuration of additive designing for electrolyte engineering in stable ZIBs. [ABSTRACT FROM AUTHOR]

Silicon‐based materials are regarded as the most promising negative electrode materials for next‐generation high‐energy lithium ion batteries due to their high theoretical capacity, low lithiation plateau and low cost, but they still suffer from dramatic volume variation during charge/discharge and sluggish kinetics, substantially restricting their practical applications. Recently, 2D MXenes are demonstrated to improve the electrochemical performances of Si‐based materials owing to their metallic conductivity, large surface aspect ratio, rich surface chemistry, good mechanical strength, etc. Serving as conductive host, MXenes can alleviate the volume expansion of Si during lithiation, enhance the electronic conductivity of the composite and facilitate the electron/ion transport, thus making the resultant Si/MXene composites exhibit excellent performance as negative electrodes of secondary batteries. Herein, an overview toward the recent advances of Si/MXene nanocomposites is presented for lithium storage applications. The preparation strategies and structural characteristics of the Si/MXene nanocomposites are introduced. The applications of diverse Si/MXene nanostructures such as powders, 3D architectures, films and fibers, in lithium ion batteries with corresponding structure‐performance relationships are discussed. Finally, the challenges and perspectives for the future research of Si/MXene nanocomposites are highlighted, aiming to provide a fundamental reference in designing advanced Si/MXene nanocomposites for high‐energy lithium ion batteries. [ABSTRACT FROM AUTHOR]

The large‐scale deployment of aqueous Zn‐ion batteries is hindered by Zn anode instability including surface corrosion, hydrogen gas evolution, and irregular Zn deposition. To tackle these challenges, a polyhydroxylated organic molecular additive, trehalose, is incorporated to refine the solvation structure and promote planar Zn deposition. Within solvation structure regions involving trehalose, the hydroxy groups participate in the reconstruction of hydrogen bond networks, which increases the overpotential for water decomposition reaction. Moreover, at the Zn metal–molecule interface, the chemisorption of trehalose onto the surface of the zinc anode enhances corrosion resistance and facilitates the deposition of zinc in a planar manner. The optimized electrolyte significantly improves Zn striping/plating reversibility and maintains stable potentials over 1600 h at 5 mA cm−2 with a cutoff capacity of 1 mA h cm−2 in symmetric cells. When combined with the MnO2 cathode, the assembled coin cell retains ≈89% of its capacity after 1000 cycles. This organic molecule additive, emphasizing the role of polyhydroxylated organic molecules in fine‐tuning solvation structures and anode/electrolyte interfaces, holds promise for enhancing various aqueous metal batteries. [ABSTRACT FROM AUTHOR]