Thin film metallic catalyst coatings for the growth of multiwalled carbon nanotubes by pyrolysis of xylene Original Research Article

Thin film metallic coatings applied to alumina and silicon substrates are investigated for their use as a catalyst to help grow high-quality multiwall carbon nanotubes (MWNTs). Substrate coatings examined include Fe, Tb:Fe, Ni, Cu, and Ni:Fe, with xylene used as the hydrocarbon source. Coating the substrate with Tb90Fe10 and Ni80Fe20 facilitated dense and uniform growth of MWNTs without graphitic particles; Ni and Fe substrate coatings produced graphitic particles in addition to the MWNTs, while Tb and Cu were found to be completely inactive with no MWNT growth. Many of the MWNTs grown over Ni:Fe have a helical appearance, while the MWNTs grown over Tb90Fe10 did not contain catalyst particles