Study of Au synthesized SWNTs mechanism by in-situ spectroscopy

Optical emission spectra (OES) of a CH4-H2 plasma during synthesis of single walled carbon nanotubes (SWNTs) using an Au catalyst were in-situ examined for the purpose of understanding the formation mechanism of SWNTs over the Au catalyst. From OES analysis, it was shown that changing the hydrogen related radicals, which are re- garded as etching species in SWNTs growth by varying the H2 flow rate made effects on the diameter and yield of the SWNTs. Also OES investigations during the SWNTs growth suggest that CH/H?can be useful for finding the optimum condition for the SWNTs growth by plasma chemical vapor deposition (PCVD) method.