Morphology and microstructure of carbon nanotubes grown by hot filament chemical vapor deposition

In this study, carbon nanotubes growth on Ni foil using hot filament chemical vapor deposition is reported. The effects of C/sup 2/H/sup 2/ concentration, deposition time, temperature and working pressure on CNTs growth were investigated. The morphology and microstructure of the films were measured and analyzed by scanning electron microscope and the graphitized structures were confirmed by Raman spectra. Deposition temperature followed by deposition time had the most significant effect on carbon nanotube length. An increase in film thickness suffered from reducing density in the case of increased C/sup 2/H/sup 2/ concentration, deposition time and deposition temperature. Higher working pressure led to the growth of denser and longer nanotubes.