Highly aligned coiled nitrogen-doped carbon nanotubes synthesized by injection-assisted chemical vapor deposition

Abstract

Large quantities of coiled nitrogen-doped carbon nanotubes with high purity and uniform diameter of approximately 25nm have been synthesized by pyrolysis of pyridine with the assistance of sublimated melamine using injection-assisted chemical vapor deposition. The coiled tubes were vertically aligned with high regularity over large areas. The pitch and coil diameter varied between (1.1–1.3μm)/revolution and 0.4–0.5μm, respectively. The overall nitrogen concentration of the coiled carbon nanotubes has been measured to be approximately 3.5%. We suggest that the growth mechanism of these coiled nitrogen-doped carbon nanotubes are related to asymmetric growth rates resulting from sublimated melamine.