Synthesis of hierarchical ZnV2O4 microspheres and its electrochemical properties

Abstract

Hierarchical ZnV₂O₄ microspheres were synthesized using an ethanol thermal reduction route for the first time, in which vanadium with a low valence can be formed. ZnV₂O₄ microspheres were characterized by X-ray diffraction (XRD), thermogravimetric analysis (TG), transmission electron microscopy (SEM/TEM) and N₂ adsorption–desorption measurements. Furthermore, this material was used as an anode for Li ion intercalation and exhibited high reversible capacity, high rate performance, and good cycling stability. For instance, a high reversible capacity of 638 mA h g⁻¹ was maintained after 280 cycles at a current density of 100 mA g⁻¹. These results might be attributed to the facts that hierarchical ZnV₂O₄ microspheres could buffer the strain and volume changes during the charge–discharge cycling process, and provide more sites for Li ion storage and a shorter path for Li ion diffusion, leading to improved capacity and high rate performance.