| 초록 |
Carbon nanotubes are expected to have a wide variety of interesting properties. The Synthetic methods for multiwalled carbon nanotube (MWNT) and singlewalled carbon nanotube (SWNT) with high purity by arc discharge have been investigated. The diameter of synthesized MWNTs was from 10 to 30nm. SWNTs were prepared by catalytic arc discharge. The discharge current of 75A was applied between two electrodes under helium (100~500Torr). The transition metals such as Ni, Co, Fe were used as catalysts. The total amount of catalysts in a graphite powder was from 5% to 15%. It was found that the yield of the nanotubes tends to increase as the gas pressure increase. And the yield of the nanotubes was higher when the total amount of catalysts was 5%, and enhanced by catalyst, Ni. To obtain the high purity, the synthesized MWNTs were purified under Air gas and the SWNTs were purified by combining two-step processes of acid treatment and thermal annealing. |
