Favorable Desolvation and Uniform Zn Deposition of Silica Modified Zn Anode for High Performance Aqueous Zn‐Ion Batteries
Wangsheng Yuan, Kai Jin, Shanbao Zou, Yishan Jin, Yishuang He, Xinhai Yuan, Peng Han, Lijun Fu, Yuping Wu
Abstract
Abstract The instability of Zn anode resulting from corrosion and dendritic growth remain impeding the development of aqueous zinc‐ion batteries (AZIBs). In addition, the desolvation on the Zn surface is sluggish, which hinders the reaction kinetics and fast charge/discharge behavior of AZIBs. Herein, the uniform Zn deposition and fast desolvation are realized by using a hydrophilic fumed nano‐silica coating with zinc alginate (Alg) as a functional binder (Alg/SiO 2 @Zn). Combined theoretical calculation and experimental investigations show the interaction between the H 2 O in the solvation structure and ‐OH functional group of SiO 2 facilitates the desolvation process. In addition to the Zn 2+ guiding effect of Alg, the fast Zn 2+ diffusion along SiO 2 endows the homogeneous Zn deposition. Consequently, Alg/SiO 2 @Zn symmetric cell demonstrates exceptional plating/stripping reversibility and excellent long‐term cycle life at both 1 and 10 mAh cm −2 . A full cell assembled with Alg/SiO 2 @Zn and NaV 3 O 8 · x H 2 O cathode achieves a high capacity of 129 mAh g −1 at 4 A g −1 over 2650 cycles. Even under −20 °C, the battery maintains a high capacity of 136.5 mAh g −1 at 1 A g −1 after 1000 stable cycles. This study provides a facile strategy to achieve a highly stable Zn anode and gains deep insight into desolvation modulation via surface modification.