The Lattice Distortion, Defect Evolution and Electrochemical Performance Improvement in Zn-VO₂(B) Nanorods

Cathode materials of energy storage batteries have attracted extensive attention because of the importance in deciding the rate performance and long cycle property of batteries. Herein, we report a simple and environmentally friendly solvothermal method to prepare Zn-doped VO₂(B) cathode materials. The introduction of zinc ions can effectively regulate the lattice structure, surface morphology and internal defect state of Zn-VO₂(B) nano materials. The sample with Zn content x = 1.5% has smaller cell volume and grain size, and higher concentration of vacancy defects. These microstructures ensure the structural stability during ion embedding process and, thus, this sample shows excellent electrochemical performances. The capacitance retention rate still maintains 88% after 1000 cycles at the current density of 0.1 A·g^-1. The enhanced performances of Zn-doped VO₂(B) samples may lay a foundation for the improvement of electrochemical performances of VO₂(B) cathode materials for energy storage batteries in the future.