AVS 50th International Symposium
    Nanotubes Wednesday Sessions
       Session NT-WeP

Paper NT-WeP7
Growth of Cone-shaped Carbon Nanotubes by Arc Discharge in Anode

Wednesday, November 5, 2003, 11:00 am, Room Hall A-C

Session: Poster Session
Presenter: S.-C. Kung, Industrial Technology Research Institute,Taiwan
Authors: S.-C. Kung, Industrial Technology Research Institute,Taiwan
C.-M. Hsu, Industrial Technology Research Institute,Taiwan
B.-J. Li, Industrial Technology Research Institute,Taiwan
H.-J. Lai, Industrial Technology Research Institute,Taiwan
Correspondent: Click to Email
Various synthetic methods are developed and the main method for the production of high quality CNTs (carbon nanotubes) is the DC (direct current) arc discharge between two graphite electrodes in a buffer atmosphere which is usually is helium, leading to the formation of nanotube-containing deposit on the end of the cathode. Many factors such as the velocity distribution of carbon ions, the density of carbon vapor, and the growth temperature have been suggested to affect the growth of CNTs. The pressure of carrier gas in the evaporation chamber is generally considered as the most important factor. Here, we report the production of CNTs without catalytic metals by DC arc discharge between two graphitic rods of the same diameter at the low pressure ambiance (ca. 10@super -2@ torr) and higher pressure helium atmosphere (ca. 900 torr). After the arcing was carried out, CNTs were discovered in the deposit on the anode instead of the cathode in low pressure working ambiance. The morphologies of CNTs on the anode deposit are specifically cone-shaped, 15 nm in diameter. The difference of nanometirc graphitic structures synthesized under the noble and higher vacuum atmosphere were discussed and characterized by FESEM, HRTEM, RAMAN spectrometer, TGA, and field emission properties measurement.