Cellulose‐Acetate Coating by Integrating Ester Group with Zinc Salt for Dendrite‐Free Zn Metal Anodes

Abstract Zinc (Zn) metal is considered a potential anode owing to its high theoretical capacity, safety, and low cost. However, the dendrites and corresponding side reactions in aqueous electrolytes hinder their further development in environmentally‐friendly energy storage. Herein, ion‐affiliative cellulose acetate (CA) coating with Zn(CF 3 SO 3 ) 2 is constructed on Zn anode (CAZ@Zn). Owing to the complexation effect between the polar ester group (CO) and Zn salt (Zn 2+ ), the CAZ polymer coating enhances the hydrophilicity of the Zn anode and reduces the interfacial resistance, allowing the rapid Zn 2+ diffusion and homogenizing the Zn deposition in an aqueous electrolyte to suppress zinc dendrite formation and growth. Therefore, the symmetric CAZ@Zn//CAZ@Zn battery achieves reversible plating/stripping over 2800 h at 1 mA cm −2 with 1 mAh cm −2 , about sevenfold higher than bare Zn. The full cell fabricated with an optimized Zn anode and the NH 4 V 4 O 10 cathode achieves substantially stable performance, superior to that of bare Zn. This work provides a straightforward, effective, and scalable method to suppress the zinc dendrites and corresponding side reactions for aqueous Zn‐ions batteries.