利用化学气相沉积法并通过控制反应温度制备了3种不同管径的碳纳米管。通过X射线粉末衍射、场发射扫描电子显微镜和场发射透射电子显微镜对样品的微观形貌和结构进行表征。利用循环伏安和恒电流充放电研究了碳纳米管电极材料的电化学性能。结果表明，反应温度越高，碳纳米管的管径越大，比电容越低。管径最小的碳纳米管在0.5 A/g电流密度下的比电容最高，达到了42 F/g。

Through controlling reaction temperature,three kinds of carbon nanotubes with different diameters are successfully prepared by chemical vapor deposition method.The microstructure and morphology of the prepared carbon nanotubes are characterized by XRD,SEM and TEM,and the electrochemical performances are also studied by cyclic voltammetry,and constant current charge and discharge methods.The results indicate that the diameters of carbon nanotubes become larger and the specific capacitance of that decreases gradually when the reaction temperature increases.The carbon nanotube with the smallest diameter has the highest specific capacitance of 42 F·g^-1 at a current density of 0.5 A·g^-1.