THE INFLUENCE OF REACTION TEMPERATION ON THE PREPARATION OF CARBON NANOTUBES

Carbon nanotubes were synthesized from methane using a NiO/SiO 2 nanosized catalyst. The results indicated that the reaction temperature had an important influence on the yield, purity and morphologies of the nanotubes. A comparative study showed that the yield was low when the reaction temperature was too low or too high. The suitable temperature for the growth of carbon nanotubes was found in the range of 620?℃～720?℃, where 660?℃～ 680?℃ was the range in which carbon nanotubes could grow stably. TEM showed that the carbon nanotubes had an inhomogeneous morphology and contained many impurities when the reaction temperature was too high or too low, the suitable temperature range was 640?℃～680?℃ for high purity.