Structure transformation by sp 2 hydrocarbon assisted carbon nanotube growth.

In this study, we investigated the effect of hydrocarbon species composition on carbon nanotube (CNT) growth using an iron catalyst by chemical vapor deposition. The atomic hydrogen and active carbon species from hydrocarbon affect to the nucleation and growth of CNT arrays. With increasing atomic hydrogen content, the interface layer distance of the CNTs decreased from 3.7 to 3.4 Å. The shifts in the G-band in the Raman spectra of the CNTs indicated that the hydrogen atoms affected the generation of C-C bonds in graphene layers.