论文部分内容阅读
用透射电镜、高分辩透射电镜、X射线衍射和拉曼光谱表征了用催化热解法制备的纳米碳管的结构 ,研究了纳米碳管的电化学嵌脱锂性能。以纳米级铁粉为催化剂热解乙炔气得到的纳米碳管石墨化程度较低 ,结构中存在褶皱的石墨层、乱层石墨和微孔等缺陷 ,具有较高的贮锂容量 ,初始容量为 640mAh/g ,但循环稳定性较差。而以纳米级氧化铁粉为催化剂热解乙烯得到的纳米碳管结构比较规则 ,循环稳定性较好 ,但贮锂容量较低 ,初始容量为 2 82mAh/g。讨论了纳米碳管的结构对其温度特性和不同电流密度下的充放电容量的影响。
The structure of carbon nanotubes prepared by catalytic pyrolysis was characterized by transmission electron microscopy, high resolution transmission electron microscopy, X-ray diffraction and Raman spectroscopy. The electrochemical intercalation and deintercalation properties of carbon nanotubes were investigated. Carbon nanotubes obtained by pyrolysis of acetylene gas with nano-sized iron powder as catalysts have a relatively low degree of graphitization, and there are defects such as wrinkled graphite layers, chalky graphite and micropores in the structure, and have higher lithium storage capacity with an initial capacity of 640mAh / g, but poor cycle stability. However, the structure of carbon nanotubes obtained by pyrolysis of ethylene with nano-sized iron oxide powder is comparatively regular, and the cycle stability is good, but the lithium storage capacity is relatively low, with an initial capacity of 2 82 mAh / g. The effect of the structure of carbon nanotubes on the temperature characteristics and charge-discharge capacity at different current densities was discussed.