PRODUCTION OF CARBON NANOTUBE BY ELECTRIC ARC DISCHARGE METHOD

Carbon nanotubes (CNT) are recently discovered allotrope of carbon. They take the form of cylindrical carbon molecules and have novel properties that make them potentially useful in wide variety of applications. Nanotubes are cylindrical in shape with at least one end capped in a spherical shape.

Carbon nanotubes can be manufactured by different process like electric arc discharge method, laser ablation method, CVD process, sol-gel method, gas phase metal catalyst and plasma enhanced hot filament CVD. We are proposed to produce carbon nanotubes by electric arc discharge method. This method creates CNTs through arc vaporization of two carbon rods placed end to end, separated by approximately 1mm, in an enclosure that is usually filled with inert gas at low pressure. A direct current of 50 to 100A, driven by a potential difference 20V, creates a high temperature discharge between the two electrodes. The discharge vaporizes the surface of one of the carbon electrodes, and forms a small rod shaped deposit on the other electrode.

Producing CNTs in high yield depends on the uniformity of the plasma arc, and temperature of the deposit forming on the carbon electrode. This method is simple, ease of construction, low cost, and availability of raw materials.