Carbon nanotubes and a-C films simultaneously fabricated by thermal CVD

Carbon nanotubes, carbon nanowires and amorphous carbon (a-C) films were simultaneously synthesized by thermal chemical vapor deposition (CVD) and the relationship between the carbon deposits and catalytic metals was studied. The Ni-coated substrates became black at lower fabrication temperature in comparison with substrates without Ni films. The deposits on the Ni-coated substrates consisted of nanotubes, nanowires and a-C grains, while those without Ni films mostly formed a-C films with nanowires sporadically distributed. The result is explained in terms of the promotion of carbon deposits by the Ni catalyst and suggests that the material phases of carbon are controllable with the catalytic effects.