Zn–Sn interface layer design strategy towards high-stability Zn powder anode

Zn powder anodes hold great promise for aqueous zinc-ion batteries (AZIBs) owing to their structural tunability, facile processability, and cost-effectiveness. However, their practical application is hindered by severe side reactions and uncontrolled dendrite formation, leading to rapid capacity degradation. Herein, we develop a Zn powder-based anode (ZnSn@ZP) with a Zn-Sn metal interface layer, fabricated via a simple electrodeposition strategy, to achieve uniform Zn deposition/stripping. The dense Zn-Sn interphase layer effectively mitigates anode corrosion, regulates nucleation, and suppresses dendritic growth, leading to remarkable electrochemical performance. The symmetric ZnSn@ZP cell exhibits exceptional cycling stability exceeding 1500 h at 1 mA cm^-2 with an initial voltage hysteresis of 16.4 mV. The ZnSn@ZP//Cu asymmetric cell demonstrates superior average coulombic efficiency of 99.6% over 2500 cycles, indicating improved Zn deposition/stripping performance. Furthermore, the full cell assembled with the MnO₂ cathode exhibits excellent cycling performance, maintaining stable cycling for 1800 cycles even at 1 A g^-1 with negligible capacity decay. This work presents an effective, cost-effective and scalable interface engineering strategy, offering new insights for developing high-stability Zn powder-based anodes.