Feedstock-dependent nitrogen configurations of nitrogen-doped single-walled carbon nanotubes in a CVD process.

The modification of nitrogen configurations is a viable way to control the electronic properties of nitrogen-doped single-walled carbon nanotubes (N-doped SWCNTs). N-doped SWCNTs were synthesized by a conventional chemical vapor deposition process with a mixed carbon/nitrogen (C/N) feedstock. While higher feedstock flow rates promote the formation of encapsulated N2 molecules, lower flow rates show a predominance of pyridinic and graphitic nitrogen structures as revealed by X-ray photoemission spectroscopy. Therefore, the nitrogen doping in the sp2 carbon network can be controlled by the flow rate of the C/N feedstock.