Oxygen Vacancies ZnO_1–x as Anode Materials for Superior-Performance Zinc-Nickel Alkaline Batteries

Zinc-nickel (Zn-Ni) alkaline batteries have appealed extensive research interest due to their low cost, high safety, and high energy density, which are favorable competitors in zinc-based batteries. Herein, we prepared ZnO with oxygen vacancies by simple hydrothermal and high temperature reduction annealing as anode materials for Zn-Ni alkaline batteries. In comparison with pristine ZnO, the introduction of oxygen vacancies not only improves the electronic conductivity of the material but also effectively provides more active sites for the reaction and lowers the ion transport energy barrier, thus improving the electrochemical reaction kinetics of ZnO_1–x. A variety of experimental results and density functional theory calculations show that ZnO_1–x has good electrochemical properties. Consequently, the synthesized ZnO_1–x anode material exhibits a specific capacity of 590 mA h g^–1 at 5 C (90% retention over 800 cycles) and excellent rate performance (612 mA h g^–1 at 10 C). Significantly, this work provides new insights into the development of anode materials for long cycle life and high rate performance.