Strategies of structural and defect engineering for high-performance rechargeable aqueous zinc-ion batteries

Abstract

Aqueous zinc-ion batteries (ZIBs) have been increasingly studied in recent years due to their low cost and high safety and the high abundance of natural zinc resources. However, the practical application of ZIBs has been restricted due to some challenges, including the low electrochemical activity of their cathodes, sluggish diffusion kinetics of Zn²⁺, structural instability during long-term cycling, formation of dendrites and occurrence of side reactions on zinc anodes. Structural and defect engineering has been developed to address these challenges. Herein, recent progress regarding the structural and defect engineering of aqueous ZIBs is summarized, mainly focusing on introducing interlayer ions/molecules and vacancies/defects into the cathode crystal structure, designing amorphous structures and/or heterostructures of cathodes, decorating an inorganic/organic coating on cathodes, creating an artificial interfacial layer on anodes and constructing nanostructured anodes. Additionally, advanced techniques in structural and defect engineering that are used for aqueous ZIBs are further summarized. Furthermore, the existing challenges and future prospects of the structural and defect engineering of ZIBs are discussed.