Effects of plasma conditions on the growth of single-walled carbon nanotubes from nonmagnetic catalysts

This paper describes experimental research on synthesis of single walled carbon nanotubes (SWNTs) from nonmagnetic catalysts with plasma chemical vapor deposition (PCVD). Nonmagnetic metal particles were found to have catalytic activity for the growth of SWNTs under a specific plasma condition. An actinometry method based on optical emission spectroscopy (OES) measurements was also used to determine the molar fraction of monoatomic hydrogen and carbon species produced in plasma. We found that Methane conversion is remarkably promoted using plasma which enhances growth of SWNTs over nonmagnetic catalysts. It is well known that metals such as Au, Ag, and Pt have low adsorption and dissociation for catalytic reactions. Hence external forces such as methanehydrogen discharge is required for high dissociation of hydrocarbons. Plasma–catalyst reaction system is able to generate desired reactants for SWNTs growth from nonmagnetic catalysts.