In-situ construction of a multifunctional Sb/ZnF2 hybrid coating via displacement reaction for highly stable aqueous zinc-ion batteries

Abstract

Aqueous zinc-ion batteries, owing to their inherent safety and cost-effectiveness, hold great promise for large-scale energy storage systems. However, their practical application remains hindered by dendrite formation, hydrogen evolution reaction (HER), and other parasitic reactions at the zinc anode. Herein, we propose a facile and efficient pre-treatment strategy for the zinc anode involving the fabrication of a compact and durable multifunctional surface layer via a displacement reaction between Zn and SbF 3 . This multifunctional layer comprises antimony (Sb) and zinc fluoride (ZnF 2 ) on the metallic zinc substrate. In this configuration, Sb exhibits high affinity for Zn and a high overpotential for hydrogen evolution, while ZnF 2 provides radial ion transport channels. Consequently, this interfacial layer effectively suppresses dendrite growth, HER, and other water-induced side reactions on the zinc metal electrode. Experimental results demonstrate a substantial enhancement in the performance of Zn-ion batteries. In particular, Zn||Zn symmetric cells incorporating this modified anode achieve stable cycling for over 180 h at a current density of 1 mA cm −2 and an areal capacity of 1 mAh cm −2 .