Construction of desolvated ionic COF artificial SEI layer stabilized Zn metal anode by in-situ electrophoretic deposition

Abstract

Aqueous zinc-ion batteries (AZIBs) have attracted tremendous attention due to their cost-effectiveness, environmental-friendliness, and intrinsic safety. However, the spontaneous surface corrosion and uncontrolled dendrite growth of AZIBs severely restrict its practical application. Herein, we develop an artificial solid electrolyte interphase (SEI) with ionic covalent-organic-framework (iCOF) nanosheets for Zn anode protection. The iCOF nanosheets form an artificial SEI layer with porous and abundant zincophilic sites through in-situ electrophoretic deposition (ED) technique, which allows for efficient mass and charge transfer. The iCOF-ED SEI layer not only facilitates a uniform Zn2+ flux but regulates the Zn2+ solvation shell, resulting in a stable and homogeneous Zn2+ deposition. This novel iCOF-ED SEI layer enables high stability for over 1000 h (with ultralow overpotential ∼ 50 mV) at 1 mA cm−2 in symmetric cells and enhances cycling stability over 1100 cycles (with high average coulombic efficiency of 99.9 %) at 2 A g−1 in half cells. This finding provides a facile and promising route for the scalable production of anodes with artificial SEI, thus promoting the development of high-performance AZIBs.