Role of thin Fe catalyst in the synthesis of double- And single-wall carbon nanotubes via microwave chemical vapor deposition

The synthesis of aligned single- and the double-wall carbon nanotubes (CNT) was presented using microwave plasma-assisted chemical vapor deposition with C ₂H ₂/NH ₃ gas mixture. The double- and single-wall carbon nanotubes with diameters ranging from 1 to 5 nm were identified using transmission electron microscopy and Raman spectroscopy. It was found that the higher deposition temperature with a controlled Fe catalyst and rapid growth allows growth of well-graphitized, high areal density nanotubes with reduced amorphous carbon and iron. The results show that the base growth is appropriate model to describe the growth mechanism for the nanotube films.