In-situ construction of a desolvation-regulated interface for a stable zinc metal anode

The zinc anode in aqueous zinc-ion batteries (AZIBs) is plagued by several critical challenges, including rampant dendritic propagation, anodic corrosion, hydrogen evolution reaction (HER), and interfacial side processes, which severely impede their practical application. In this work, a simple in situ self-construction strategy is developed to directly form an artificial ZnCr2O4 (ZCO)-based solid electrolyte interphase (SEI) layer on the surface of the zinc anode. The resulting ZCO@Zn electrode effectively mitigates parasitic reactions at the solid-liquid interface. Systematic characterizations and electrochemical evaluations reveal that the ZCO layer endows the zinc surface with enhanced hydrophilicity, facilitating improved electrolyte wettability and more homogeneous zinc deposition. Meanwhile, the modified anode presents a higher corrosion potential (Ecorr) and a reduced HER overpotential, indicating suppressed corrosion and hydrogen evolution. Consequently, symmetric cells assembled with ZCO@Zn deliver outstanding cycling stability, operating steadily for over 2800 h at 1 mA cm-2 and 1 mAh cm-2, and maintaining stable performance for over 1500 h under higher current densities. Additionally, when coupled with an NH4V4O10 cathode, the full cell demonstrates outstanding long-term cycling performance, retaining 94.03% of its initial capacity after 2000 cycles. This work presents a facile and effective surface engineering strategy for zinc metal anodes, offering valuable insights for the design of durable, high-performance AZIBs.