Construction of an n-Type Fluorinated ZnO Interfacial Phase for a Stable Anode of Aqueous Zinc-Ion Batteries

Aqueous rechargeable zinc-ion batteries have become an ideal solution for the next generation of energy storage systems due to their low cost and high safety. However, the uncontrollable zinc dendrites and harmful side reactions of metal zinc anodes hinder the further development of aqueous zinc-ion batteries. In this work, the artificial fluoride zinc oxide (F-ZnO) interface phase is integrated in situ on the surface of zinc foil. The F-ZnO interface phase significantly inhibits the side reactions on the surface of the zinc electrode by reducing the direct contact between the electrolyte and the surface of the zinc foil. In addition, F-ZnO modified by a small amount of F doping shows enhanced conductivity and electron transport capacity, avoiding the accumulation of high concentration Zn²⁺ on the anode surface, and ultimately promoting the efficient nucleation and orderly deposition of a zinc anode. The cycle life of the symmetrical cell based on F-ZnO is as high as 2600 cycles at an area current density of 4 mA cm^-2, which is much better than that of a commercial pure Zn electrode. The modified F-ZnO@Zn anode truly achieves the purpose of prolonging the anode's life.