Growth of multi-walled carbon nanotubes by nebulized spray pyrolysis of a natural precursor: alpha-pinene.

Multi-wall carbon nanotubes (MWCNT) were prepared by spray-pyrolysis of alpha-pinene, a botanical hydrocarbon, and ferrocene as catalyst at 900 degrees C. The MWCNT were analyzed by scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), and Raman spectroscopy. The microscopy studies show the formation of carbon nanotubes with diameters between 20 and 30 nm and length greater than one hundred microns. Nanoparticles were detected outside and inside the nanotubes and were identify as metallic iron and iron carbide, respectively. Raman spectroscopy reveals that the alpha-pinene grown carbon nanotubes are graphitized showing both the D and G bands at 1335 cm(-1) and 1585 cm(-1) respectively.