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ZnO@SnO 2 micron flowers with loose and porous surfaces are obtained by a one-step hydrothermal process. This flower-like structure of stacked sheets expands the contact area for electrode reaction and reduces the current density, which helps to suppress polarization. In addition, Sn increases the electrical conductivity of the material and hydrogen evolution overpotential of the electrode, resulting in a great improvement in the utilization of the anodic material. The design of this anode composite can effectively solve the problems of short cycle life and poor cycle performance of zinc-based batteries to a certain extent. According to this study, the ZnO@SnO 2 electrode is still able to achieve a discharge specific capacity of 539 mAh•g −1 after 1000 cycles, which is 92.3% of the initial discharge specific capacity (584 mAh•g −1 ). Flower-like ZnO@SnO 2 has excellent cycling performance at high rates as an anodic material for zinc−nickel secondary 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.

Antimony-doped tin oxide (ATO) is prepared by a co-precipitation method and used as a nano-conducting layer for surface modification of spherical zinc oxide to obtain ZnO@ATO composites with excellent properties. As an anode material for zinc–nickel batteries, ZnO@ATO exhibits superior performance in terms of cycle life and stability, which is attributed to the optimization effect of ATO on the ZnO electrode. ATO increases the conductivity and specific surface area of the anode material, accelerates the electron transfer, and homogenizes the current density on the electrode surface so that the polarization effect in the electrode reaction is effectively suppressed. According to the electrochemical test results, ZnO@ATO as an electrode material still maintains a discharge specific capacity of 561.8 mAh·g–1 after 1950 cycles, which is 96% of the initial discharge specific capacity (583.6 mAh·g–1), demonstrating excellent cycle life and capacity retention.

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