Suppressing Corrosion and Side Reactions of Zinc Metal Anode by CoWO ₄ Coating Toward High‐Performance Aqueous Zinc‐Ion Batteries

Aqueous zinc‐ion batteries (AZIBs) have attracted increasing attention due to their advantages of low cost and high safety, as well as their high bulk energy density. Nevertheless, serious corrosion and dendritic growth of zinc anode during cycling, as well as anode–electrolyte side reactions primarily restrict the large‐scale applications of AZIBs. To address these issues, herein, an artificial CoWO ₄ protective layer was coated on the surface of zinc metal anode via the blade method. Results showed that this hydrophobic coating layer could effectively inhibit the direct contact of Zn metal anode with electrolyte, suppressing its corrosion and side reactions during Zn deposition and stripping. Benefiting from this advantage, the CoWO ₄ @Zn anode could steadily cycle for 200 cycles with a high average Coulombic efficiency in the half‐cell test at a current density of 0.5 mA cm ⁻² . The symmetrical battery with CoWO ₄ @Zn electrode could cycle for 2700 h with a low overpotential at 0.25 and 0.05 mAh cm ⁻² . In addition, when assembled with Mn‐ and V‐based cathodes, the cell with CoWO ₄ @Zn anode exhibited better cycling stability than bare Zn anode. Thus, this strategy brings new opportunities for the future development of rechargeable AZIBs.