The negative effects of alcohols on carbon nanotube synthesis in a nebulised spray pyrolysis process

Multi-walled carbon nanotubes were synthesized by the nebulised spray pyrolysis (frequency 1.6 MHz) of toluene and toluene–alcohol mixtures with ferrocene as the catalyst precursor. The CNTs produced were characterized by TEM, SEM, Laser-Raman spectroscopy and TGA. The results show that the presence of ethanol, 2-propanol and octanol in the reaction mixture reduces the CNT yield, growth rate and produces CNTs that are less well graphitized and less resistant to oxidation. The data suggests that the exposure of the alcohol-containing mixture to ultrasound irradiation results in the production of radicals that inhibit CNT formation.