Growth mechanism of carbon nanotubes in methane diffusion flames Original Research Article

Straight and bamboo-like carbon nanotubes were synthesized in a methane diffusion flame using a Ni–Cr–Fe wire as a substrate. The catalyst particles were nickel and iron oxides formed on the wire surface inside the flame. When the wire was oxidized using nitric acid more nanotubes could be produced. Most nanotubes grew by a base growth mode. The formation of bamboo-like nanotubes was related to the shape of the catalyst particles. A segregation growth mechanism of bamboo-like nanotubes is proposed.