查看文章

This study aims to investigate effect of pre-heating of pure CH₄ on the growth of C nanotubes by chemical vapor deposition in the presence of Fe–Ni (70wt.%) alloy catalyst. It was observed that un-preheated CH₄ yielded no C formation at 1050–1150K owing to its poor decomposition rate, contrary to the results of thermodynamic analysis. Whereas, pre-heating treatment of CH₄ at 1200K prior to the growth increased pyrolysis of the hydrocarbon which promoted synthesis of C nanotubes at 1050–1150K, possibly due to enhanced formations of intermediate gaseous species. TEM study revealed that the morphologies of the products consist of multi-walled C nanotubes.