A silver paste engineered interphase enables highly reversible and dendrite-free Zn metal anodes

Abstract

The main bottleneck of aqueous zinc metal anodes is the limited cycle lifespans stemming from severe dendrite formation and fragile interfaces. Herein, we fabricated a silver paste protective layer on a Zn substrate surface via a spray-coating technique, creating a versatile interphase that enables highly reversible and corrosion-resistant Zn anodes. The commercial silver paste, composed mainly of Ag and Cu particles, forms a zincophilic composite layer that facilitates uniform Zn-ion flux. The Ag/Cu surface could effectively suppress the hydrogen evolution reaction due to the high hydrogen evolution barrier, thereby suppressing interfacial side reactions caused by water. Notably, the Ag–Zn and Cu–Zn alloys formed during the early plating/stripping processes regulate zinc nucleation without dendrite formation and facilitate ion transfer in subsequent cycles, contributing to improved coulombic efficiency and extended cycling durability. The Zn@SP symmetric cell exhibits remarkable longevity, maintaining stable operation for 3500 h at 0.5 mA cm⁻² (0.5 mA h cm⁻²). When paired with a V₂O₅ cathode, the full cell incorporating the Zn@SP anode showcases outstanding rate capability and cycling performance. This economical silver paste combined with the facile and scalable spray-coating method presents a viable pathway towards commercializing high-performance metal anodes.