Towards low-temperature dendrite-free zinc anode by constructing functional MXene buffer layer with duplex zincophilic sites.

Dendrite growth and side reactions of zinc metal anode have severely limited the practical application of aqueous zinc ion batteries (AZIBs). Herein, we introduce an artificial buffer layer composed of functional MXene (TiCN) for zinc anodes. The synthesized TiCN exhibits superior conductivity and features duplex zincophilic sites (N and F). These characteristics facilitate the homogeneous deposition of Zn, accelerate the desolvation process of hydrated Zn, and reduce the nucleation overpotential. The TiCN-protected Zn anode demonstrates significantly enhanced reversibility compared to bare Zn anode during long-term cycling, achieving a cumulative plating capacity of 10,000 mAh cm at 10 mA cm. In TiCN-Zn||Cu asymmetric cell, it maintains nearly 100 % Coulombic efficiency over 2500 cycles at 2 mA cm. Furthermore, the assembled TiCN-Zn//δ-KVO (KVO) full cell exhibit a low capacity decay rate of 0.002 % per cycle at 5 A/g. Even at 0 °C, the TiCN-Zn symmetric cell maintains steady cycling for 2000 h. This study introduces a novel approach for designing artificial solid electrolyte interlayers for commercial AZIBs.