Construction of ZnSe protective layer on zinc oxide for ultra-stable cycling of zinc-nickel batteries at high rates

Abstract

Zinc anodes suffer from self-corrosion, deformation and dendrite growth, which greatly limit the commercial application of zinc-nickel batteries. For this purpose, zinc oxide microspheres with porous surfaces are synthesized by a simple hydrothermal method, and ZnSe protective layer is constructed on their surfaces. The uniform coverage of ZnSe improves the corrosion resistance of the anode material and alleviates the polarization phenomenon during the cycle, thus ensuring the stability of the electrode material. Moreover, the prominent specific surface area optimizes the interface contact between anode and electrolyte, improving the ion transport efficiency while homogenizing the current distribution around the interface. Therefore, the discharge specific capacity of ZnO@ZnSe electrode can still reach 577.5 mAh·g−1 after 1460 cycles at a high rate. There is almost no attenuation compared with the initial discharge capacity, demonstrating an extremely excellent electrochemical performance.