In-situ construction of solid-electrolyte interface for metallic Zn anode in aqueous zinc battery

Abstract

Zn metal batteries (ZMBs) have attracted significant attention due to their high safety, cost-effectiveness, environmental friendliness, and promising electrochemical properties. However, the development of ZMBs still faces the stubborn irreversibility of Zn stripping/plating since their birth. To address this challenge, constructing robust electrolyte-Zn interface is one of the major strategies. Importantly, in-situ solidelectrolyte interface (SEI) possesses the advantages of regulating interfacial reactions and depressing side reactions. So far, the formation mechanisms of in-situ SEI have been intensely elaborated, which acquires a concurrent summary. Here, we aim to discuss the roles of in-situ SEI on rationalizing the interfacial reactions from the aspects of modulating solvation structure, guiding zinc ion flux, modifying nucleation sites, inducing uniform deposition and crystal orientation. The formation mechanisms of SEIs on Zn have been summarized including replacement, precipitation, decomposition, polymerization, combination, and adsorption/self-assembly, with the surface material characteristics and corresponding functions. Further, perspectives on understanding the SEI formation mechanisms with ideal intrinsics are provided. We anticipate this minireview can motive comprehending the underlying chemistry for novel SEI design.