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The limited lifespan of aqueous zinc‐ion batteries (with vanadium‐oxide based cathodes) is constrained by practical applications due to corrosion accelerated by vanadium ions leaching from the cathode and uneven dendrite growth on the zinc metal anode. To address these issues, the difference in size between hydrated zinc ions (4.30 Å) in electrolyte and vanadium ions (8.34 Å) is considered. Uniformly coating the MOF‐801 nanoparticles (with a pore size of 6.0 Å) on the zinc foil formed a selective ion transport layer. The uniform zinc ion flux generated by the selective ion transport layer allows hydrated zinc ions to be transported evenly and promotes uniform zinc deposition, leading to a low overpotential (17.4 mV) and high cycle stability (1000 h) in the symmetric cell. Moreover, the selective ion transport layer, having pores smaller than vanadium ions, blocked vanadium ions from migrating toward the zinc anode, thereby reducing its corrosion and contributing to a capacity retention of 86% after 2000 cycles under full‐cell conditions. This study demonstrates that the pore size of the coating layer influences the long‐term stability of aqueous zinc‐ion batteries and may serve as a guide when selecting interface modification materials for various metal batteries. [ABSTRACT FROM AUTHOR]

High‐entropy spinel oxides (HESOs) are a promising class of electrocatalysts whose material properties and catalytic activity can be finely tuned by controlling the elemental composition. Although numerous HESOs are already reported, their compositions are primarily limited to the first‐row transition metals. Herein, the synthesis of a high‐entropy spinel (CrFeCoNiMo)3O4 nanosheet (HEO‐NS) and its application as oxygen evolution reaction (OER) catalyst are reported. The high‐entropy spinel displays a low overpotential of 255.3 mV at a current density of 10 mA cm−2 and excellent stability, outperforming the IrO2 benchmark. Careful analysis with X‐ray photoelectron spectroscopy (XPS) and X‐ray absorption spectroscopy (XAS) reveals that the incorporation of high‐valence Cr and Mo can activate the lattice oxygen by weakening the metal–oxygen bond and promoting the lattice oxygen mechanism (LOM). Furthermore, the catalyst can achieve a high current density of 1 A cm−2 at 1.71 V in a lab‐scale electrolyzer, demonstrating the potential of HESOs for practical application. [ABSTRACT FROM AUTHOR]

The electrochemical carbon dioxide reduction reaction (eCO2RR) has great potential in addressing environmental and renewable energy storage issues simultaneously. However, highly valuable C2+ products are usually obtained at high overpotentials with low Faradaic efficiencies owing to the sluggish kinetics of C–C coupling of the reaction intermediates, especially in neutral electrolytes. Recently, oxide-derived copper (OD-Cu) has attracted significant attention for its high selectivity toward C2+ products in the eCO2RR. While various CuOx precursors have been reported to influence the reconstruction of CuOx and product selectivity, CuOx precursors with new dopants are required to understand the influence of metal dopants. Here, we synthesized Al-doped CuO (CuO_Al) using a metal–organic framework to examine the effect of Al dopants on the catalytic activity of OD-Cu. Interestingly, Al induces reconstruction of CuO_Al, forming nanoflakes, which exhibit a high Faradaic efficiency of 68.4% and a large partial current density of 478.7 mA cm−2 toward C2+ products at −1.08 V versus a reversible hydrogen electrode in a neutral 1 M KHCO3 electrolyte. Contact angle measurements and lead underpotential deposition revealed that the reconstruction provides CuO_Al with high hydrophobicity and high electrochemically active surface area, respectively. Our findings suggest that the dopant-mediated reconstruction of CuO into OD-Cu can effectively promote activity and selectivity toward C2+ products with enhanced structural properties by using small amounts of dopants. [ABSTRACT FROM AUTHOR]