The synthetic methods for high yield of multiwalled carbon nanotube (MWNT) and singlewalled carbon nanotube (SWNT) with high purity by arc discharge have been investigated. MWNTs were synthesized under different pressures of helium and the gas mixture of argon and hydrogen. Relatively high pressure of 300-400 torr was required for high yield MWNTs synthesis at low bias voltage of about 20 V and 55 A, whereas low pressure of about 100 torr was required for SWNTs. The introduction of hydrogen gases during the synthesis of MWNTs improved the yield and purity of the samples. The SWNTs were synthesized by the assistance of a small amount of mixture of transition metals, which played as a catalyst during the formation process. The purity and yield of SWNTs were higher at a lower pressure and enhanced by mixing more components of the transition metals.

• Keun-Soo Kim(Department of Semiconductor Science and Technology, Department of Physics, and Semiconductor Physics Research Center, Jeonbuk National University)
• Young-Soo Park(Department of Semiconductor Science and Technology, Department of Physics, and Semiconductor Physics Research Center, Jeonbuk National University)
• Kay-Hyeok An(Department of Semiconductor Science and Technology, Department of Physics, and Semiconductor Physics Research Center, Jeonbuk National University)
• Hee-Jin Jeong(Department of Semiconductor Science and Technology, Department of Physics, and Semiconductor Physics Research Center, Jeonbuk National University)
• Won-Seok Kim(Department of Semiconductor Science and Technology, Department of Physics, and Semiconductor Physics Research Center, Jeonbuk National University)
• Young-Chul Choi(Department of Semiconductor Science and Technology, Department of Physics, and Semiconductor Physics Research Center, Jeonbuk National University)
• Seung-Mi Lee(Department of Semiconductor Science and Technology, Department of Physics, and Semiconductor Physics Research Center, Jeonbuk National University)
• Jeong-Mi Moon(Department of Semiconductor Science and Technology, Department of Physics, and Semiconductor Physics Research Center, Jeonbuk National University)
• Dong-Chul Chung(Division of Information, Communication, and Computer Engineering, Woosuk University)
• Dong-Jae Bae(Department of Semiconductor Science and Technology, Department of Physics, and Semiconductor Physics Research Center, Jeonbuk National University)
• Seong-Chu Lim(Department of Semiconductor Science and Technology, Department of Physics, and Semiconductor Physics Research Center, Jeonbuk National University)
• Young-Seak Lee(Department of Chemical Enginnering, College of Enginnering Sunchon National University)
• Young-Hee Lee(Department of Semiconductor Science and Technology, Department of Physics, and Semiconductor Physics Research Center, Jeonbuk National University)