Synthesis, Doping and Electrochemical Properties of Zn₃V₃O₈

The Zn₃V₃O₈ was synthesized by solvothermal method combined with heat treatment using Zn(NO₃)₃ · 6H₂O and NH₄VO₃ as raw materials. The Zn₃V₃O₈ was doped by Co²⁺ to form Zn_2.88Co_0.12V₃O₈. The samples were characterized by X-ray diffraction and scanning electron microscopy techniques. Electrochemical tests showed that the initial discharge specific capacity for Zn_2.88Co_0.12V₃O₈ was 640.4 mAh·g^-1 when the current density was 100 mA·g^-1, which was higher than that of pure Zn₃V₃O₈ (563.5 mAh · g^-1). After 80 cycles, the discharge specific capacity of Zn_2.88Co_0.12V₃O₈ could maintain at 652.2 mAh · g^-1, which was higher than that of pure Zn₃V₃O₈ (566.8 mAh·g^-1) under same condition. The Zn_2.88Co_0.12V₃O₈ owned better rate performances than those of pure Zn₃V₃O₈ also. The related modification mechanisms were discussed in this paper.