High entropy electrolyte modifies electrode/electrolyte interface promoting highly reversible zinc anode

Abstract

Aqueous zinc-ion batteries (AZIBs) have drawn considerable interest owing to their affordability, safety, and eco-friendly nature. Unfortunately, the uneven deposition on the Zn anode promotes the growth of dendrites, and the corrosion of Zn by interfacial active water triggers a severe hydrogen evolution reaction (HER), which greatly hampers the further application of AZIBs. Therefore, a high-entropy (HE) electrolyte strategy is proposed to achieve a highly reversible Zn metal anode and an improved electrode/electrolyte interface (EEI). Specifically, this HE electrolyte achieves a water-poor solvation structure through N'N dimethylformamide (DMF) modulation of the solvation structure and accelerates Zn²⁺ diffusion. The dynamic adsorption processes of benzylideneacetone (BDA) and DMF adsorption on the Zn anode strengthen the electrode-electrolyte interface, promoting uniform Zn deposition and interfacial stability are achieved. Consequently, Zn||Zn symmetric cells demonstrate cycle stability exceeding 1400 h, while Zn||Cu cells achieve an average Coulombic efficiency of 99.63% over 750 cycles. In addition, full cells assembled with this electrolyte demonstrates their great potential for practical applications. This study provides a promising idea for designing high-performance aqueous high-entropy electrolytes.