Surface-Engineered Zn-Based Alloys Anodes for Aqueous Zn Batteries

Abstract

Safety and durability concerns caused by surface and interface instabilities of high-surface-activity energy materials are challenging modern electrochemical energy conversion and storage systems. In this presentation, I will present our most recent representative works on the surface engineering of functional materials for aqueous batteries. In this work, we designed an in-situ visualized protocol that can exactly mimic the actual electrochemical environments used in aqueous batteries. Using this novel protocol, we observed the dynamic processes of metal plating/stripping on the alloys in aqueous batteries. Comprehensive and systematic studies based on experimental, theoretical, spectroscopic, and microscopic approaches prove that absolute reversibility can be achieved by using the proposed 3D alloys because of the significantly improved Zn diffusion and successfully suppressed dendrite growth. As a proof-of-concept, the novel alloy structures deliver unprecedented stability with nearly 100% Coulombic efficiency over thousands of cycles even under harsh electrochemical conditions, including testing in seawater-based aqueous electrolytes and using a high current density of 80 mA cm-2.