Quaternary Alloy Interfaces for Stable Zinc Anodes for High‐Performance Aqueous Zinc‐Ion Batteries With Long‐Term Cycling Stability

Abstract Aqueous zinc‐ion batteries (AZIBs) have emerged as a promising energy storage solution owing to their intrinsic safety, low cost, environmental friendliness, and high theoretical specific capacity. However, their practical application is hindered by uncontrollable dendrite growth and side reactions at the zinc metal anode. To address these challenges, a simple and cost‐effective electrodeposition strategy is proposed to construct a quaternary Zn‐Cu‐Sn‐Bi alloy artificial interface layer on zinc foil (ZCSB@Zn) as the anode of AZIBs. Density functional theory (DFT) calculations and in situ optical dendrite observation confirm that this dense alloy interface layer reduces the migration barrier and weakens hydrogen adsorption, facilitating uniform zinc deposition while effectively suppressing side reactions and dendrite formation. The symmetric ZCSB@Zn cell exhibits extraordinary cycle stability exceeding 8000 h. Furthermore, the assembled ZCSB@Zn//CSB‐MnO 2 full cell demonstrates a high specific capacity of 199 mAh g −1 at 1 A g −1 , maintaining stability even under high loading of 10 mg cm −2 and high temperature conditions (50 °C). This study presents a scalable and cost‐effective strategy for constructing quaternary artificial interface layers in zinc metal anodes, highlighting their potential for practical AZIB applications.