采用溶剂热法制备了碳纳米管穿插的分级结构五氧化二钒空心球（VOCx）. 使用XRD、SEM、循环伏安曲线和充放电曲线研究了不同碳纳米管量对产物结构、形貌和电化学性能的影响. 结果表明，碳纳米管的加入明显改善了VOC的倍率特性. 碳纳米管含量为7.1%时，0.5 A·g-1电流密度下，其比电容达到346 F·g-1，8 A·g-1电流密度时，其电容保持率可达75%. 与活性炭组装成混合电容器，在功率密度为700 W·kg-1时，能量密度达12.6 Wh·kg-1.
The carbon nanotubes/vanadium oxides (CNTs/V2O5) hollow microspheres (VOC) were prepared via solvothermal process. The effects of the ratio for CNTs to V2O5 on the morphologies, structures and electrochemical performances were systemically investigated. The results indicate that CNTs dramatically enhanced the rate performances of VOC composite electrodes. When the ratio of CNTs is 7.1%, the VOC composite electrode exhibited the best electrochemical performance, which delivered a specific capacitance of 346 F·g-1 at 0.5 A·g-1 and maintained 75% at 8 A·g-1 in 5 mol L-1 LiNO3. A hybrid capacitor was assembly using commercial activated carbon as the negative electrode and VOC as the positive electrode. The hybrid capacitor exhibited an energy density of 12.6 Wh·kg-1 and power density of 700 W·kg-1.
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