Comparison of source gases and catalyst metals for growth of carbon nanotube

Effects of different carbon source gases and catalyst metals on the growth characteristics and emission properties of carbon nanotubes (CNTs) were investigated. As the flow rate ratio of NH3/C3H4 increased, the growth rate of CNTs was enhanced and the average diameter of CNTs became smaller. Ni was more efficient for the field emission of CNTs than any other catalyst metals when using the C2H2 gas, and in case of C3H4 as the carbon source, Co played an important role as a catalyst. When using the CO gas, Fe was the most activated catalyst for the CNTs growth under the flow rate ratio of CO/NH3 of 18. CNTs grown using different catalyst metals had their corresponding catalyst particles at the top of the tips.