Synthesis of Bamboo-like N-doped Carbon Nanotubes by Catalytic Pyrolysis of Melamine

Bamboo-like N-doped carbon nanotubes were prepared by catalytic pyrolysis method with melamine as raw material and FeCl₂·6H₂O as catalyst precursor. The effects of the reaction temperature and FeCl₂·6H₂O content on the phase composition and microstructure of the product were investigated. The results show that at the reaction temperatures of 650-800℃, the yield and length to diameter ratio of the carbon nanotubes first increased and then decreased with the increase of reaction temperature. The optimal reaction temperature was 750℃. When pyrolyzing at 750℃, the yield and length to diameter ratio of the carbon nanotubes first increased and then decreased with the increase of FeCl₂·6H₂O content and the optimal content was 0.50wt% of melamine. The obtained carbon nanotubes under this condition had diameters of 40-50 nm and lengths of 10-15 μm, the N-doping amount in the carbon nanotubes was about 3.42at%, in which the fraction of graphitic N was about 43.1mol%.