Synthesis of carbon nanotubes on a catalytic metal substrate by using an ethylene inverse diffusion flame

An ethylene fueled inverse diffusion flame was used for analyzing the synthesis of carbon nanotubes on a catalytic metal substrate. Multi-walled carbon nanotubes, with diameter of 20-60 nm, were formed on stainless steel substrate coated with nickle nitrate. The scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Raman spectroscopy measurements show that the formation temperature of carbon nanotubes and nanofibers ranged from 1300 to 800 K. The high resolution-transmission electron microscopy (HR-TEM) and Raman spectrum revealed that the nanotubes synthesized had multi-walled structures with some defective graphite sheets at the wall.