不同原料气催化热解法制备碳纳米管的研究

以CH4和C3H6为原料气，Ni-SiO2为催化剂，采用催化裂解法制备了碳纳米管。考察了两种原料气在单位催化剂上的产量与碳纳米管的转化率，并运用TEM、XRD和Raman对所获碳纳米管的形貌结构性能进行了分析。结果表明：以CH4为原料气时单位催化剂上的产率虽低而转化率却较高。说明当C1H6发生分解时，分解出来的碳只有少部分转化成了碳纳米管，而大部分为副产物；当CH4分解时，副反应较少，因此转化率较高：同时微观结构的分析也表明：采用CH4为原料气时，产物的形貌比较均一，其有序程度较高，碳纳米管的结构缺陷也较少。

The production of CNTs by catalytic decomposition of different source gases

Carbon nanotubes were prepared by catalytic decomposition of CH_4 or C_3H_6, and the effect of source gases on the yield and morphologies of the carbon nanotubes was investigated. When CH_4 is used, besides a higher conversion, the resultant carbon nanotubes have a more regular and more homogenous morphology as evidenced by TEM. The XRD patterns of the products from both source gases are similar to that of graphite, but the degree of long-range order of these nanostructures is relatively low. Compared with the carbon nanotubes produced from C_3H_6, the carbon nanotubes produced from CH_4 have a higher degree of long-range order, which suggests that CH_4 is a more suitable source gas to produce carbon nanotubes. The Raman spectrum indicates that there are more defects in the structure of carbon nanotubes produced from C_3H_6 than from CH_4.