Micro‐Hydrophobic Microstructure Balance Electric Field Distribution and Wettability for Ultra‐Stable Zinc Anodes

ABSTRACT Aqueous zinc‐ion batteries application is impeded by the intrinsic instability of zinc metal anodes, mainly attributable to dendrite growth and parasitic side reactions. Herein, micro‐hydrophobic microstructures are constructed based on the spatial confinement effect, balancing the surface electric field distribution and wettability of the zinc anode, fundamentally inhibiting zinc dendrite growth and water‐induced side reactions. A photolithography etching technique is utilized to fabricate micropillar arrays with well‐controlled dimensions. By adjusting the etching time, anodes with different pillar heights are obtained, resulting in a tunable surface wettability with contact angles spanning from 100° to 120° (designated as Zn100°, Zn110°, and Zn120°). Comprehensive analysis demonstrates a non‐monotonic correlation between wettability and performance, where the Zn100° anode achieves an optimal equilibrium, maintaining stability for over 6000 h in symmetric cells and retaining a capacity of 110 mAh g − 1 after 10 000 cycles in full cells. This study achieves a significant improvement in zinc anode performance through the combination of micro‐nanoengineering and surface regulation, not only advancing zinc‐ion batteries technology but also providing new insights for addressing issues with other metal anodes.