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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]

Sodium‐ion batteries (NIBs) are promising alternatives to lithium‐ion batteries for large‐scale energy applications such as energy storage systems, owing to the earth‐abundance and low cost of sodium resources. Among layered oxide cathode materials for NIBs, O3‐type NaCrO2 has attracted considerable attention owing to its electrochemically active Cr3+/4+, which is unlike that of LiCrO2, and potential for carbon coating with a high thermal stability. In this study, we propose a new facile and eco‐friendly method for applying nitrogen‐doped carbon to NaCrO2 using coffee waste as a carbon source. The synthesized O3‐type NaCrO2/coffee waste–derived N‐doped carbon composite exhibits an outstanding electrochemical performance as an NIB cathode material. The sodium/composite cell achieved a 73.7% capacity retention after 500 charge/discharge cycles and an approximate 50% discharge capacity during 43 s of charge. The results demonstrate the potential use of coffee waste for battery materials with improved electrochemical performances. [ABSTRACT FROM AUTHOR]