Decoupling Hydrophobicity from Zincophilicity: Liquid Metal and MBene Synergy in Cellulose Gel Electrolytes for Interface-Stabilized Zinc-Ion Storage

Abstract

To suppress the zinc dendrites and side reactions induced by free water at the gel electrolyte/anode interface and adjust the uniform distribution of zinc ions at the interface of cellulose-based gel electrolytes, an artificial functional layer (AFL) was designed by a two-dimensional transition metal boride (MBenes)/liquid metal (GaInSn) interface layer coating on the zinc foil to construct a quasi-solid-state aqueous zinc ion battery. MBene with rich oxygen terminations was prepared by a molten etching method, owing to zincophilic and hydrophilic, which could promote uniform zinc (002) plane deposition but result in severe water decomposition. The high zincophilic and hydrophobicity of GaInSn liquid metal (LM) can reduce the nucleation barrier of zinc and side reaction, as well as ensure high reversibility of the zinc anode during plating/stripping process. Decoupling hydrophobicity from zincophilicity of MBene/GaInSn interface layer could effectively prevent water molecules from contacting the zinc anode surface, inhibiting zinc metal corrosion. The symmetric cell assembled with MBene/GaInSn@Zn anode exhibited excellent long-term cycling performance (over 590 h at 1 mA cm−2/0.5 mAh cm−2). Furthermore, the ZnHCF//MBene/GaInSn@Zn full cells demonstrated a high specific capacity (83.1 mAh g−1 at 1 A g−1), excellent cycling stability (88.1% capacity retention after 1000 cycles), and good rate capability. Even at a high density of 5 A g−1, it shows a superior capacity retention rate of 89.8% after 1000 cycles.