High-Entropy Oxide Interlayers Enable Coordinated Regulation of Zn²⁺ Interfacial Kinetics for Stable Zinc Metal...

The reversibility of Zn metal anodes in aqueous zinc-ion batteries is fundamentally limited by interfacial kinetic heterogeneity, where sluggish Zn²⁺ desolvation, uncontrolled surface migration, and nonuniform charge transfer jointly trigger dendrite growth and parasitic reactions. Here, we demonstrate a conformal high-entropy spinel oxide, (CrCoFeMnNi)₃O₄, as an interfacial layer to actively regulate Zn²⁺ interfacial kinetics rather than passively blocking deposition. Electrochemical impedance spectroscopy, Arrhenius analysis, and distribution of relaxation times reveal that the high-entropy oxide simultaneously lowers the Zn²⁺ desolvation energy barrier, suppresses lateral surface migration, and stabilizes charge-transfer and diffusion processes, thereby enabling uniform Zn plating and reversible stripping. Consequently, the modified Zn anodes achieve a Coulombic efficiency of 98.26% over 400 cycles, sustain stable symmetric cell operation for over 1100 h, and maintain low polarization at current densities up to 10 mA cm^-2. When paired with NH₄V₄O₁₀ cathodes, the full cells deliver 251.5 mAh g^-1 after 1000 cycles and retain 138.1 mAh g^-1 at 10 A g^-1. This work establishes high-entropy oxide interlayers as an effective platform for mechanistically regulating Zn interfacial kinetics, offering a concise and scalable strategy for stabilizing Zn metal anodes.