Constructing a rapid ion-transport anode interface protective layer for zinc ion batteries to suppress solvation and improve surface electronic structure

Abstract

Rechargeable Aqueous Zinc-Ion Batteries (AZIBs) have attracted significant attention in recent years due to their high energy density, safety, and cost-effectiveness. However, despite these advantages, AZIBs face challenges such as anode side reactions, passivation, corrosion, hydrogen evolution, and the growth of zinc dendrites, which hinder their widespread use. To address these issues, this study involves the creation of a zinc-affinitive coating using a WSe2/ZIF composite on zinc foils. The amorphous WSe2 protective layer, formed through electrochemical induction as ZnSe, enhances the anode's zinc affinity, accelerates Zn2+ transfer at the interface, and effectively inhibits zinc dendrite growth. Additionally, the coating improves electrolyte wettability, reducing interface resistance. Compared to pure zinc, anodes with a WSe2/ZIF protective layer exhibit excellent performance in both symmetric cells and full-cell systems using MXene/MnO2 as the cathode. Symmetric cells can cycle for over 1000 h at a current density of 5 mA/cm2, and the full cell maintains a capacity retention of 91.4 % after 2000 charge-discharge cycles. This interface engineering strategy, supported by density functional theory calculations, provides a strong foundation for practical applications.