Carbon Nanotubes and its applications
Synthesis Arc evaporation method, laser ablation, chemical vapor deposition, electrolysis, flame synthesis are the various methods that are used for the synthesis of carbon nanotubes in large numbers. Arc evaporation method, laser ablation and chemical vapor deposition are the techniques which are used broadly for synthesis of CNTs. Arc evaporation method When hot plasma discharge is created between two graphite electrodes connected by a power supply of 10-20 A in the presence of inert gas such as helium gas carbon nanotubes are produced. The yield of carbon nanotubes can be increased by increasing the helium pressure inside the chamber to a certain value but beyond that value the yield of carbon nanotubes are reduced. Better quality of carbon nanotubes can be obtained by lowering the supply current. Instead of helium nitrogen and CF 4 were also used. Laser ablation method When the carbon source(graphite) is doped with small amount of ...