The effect of carbon precursors (methane, benzene and camphor) on the quality of carbon nanotubes synthesised by the chemical vapour decomposition

The effect of carbon precursors on carbon nanotube (CNT) formation was studied. The catalyst used was Fe3O4/MgO without prior reduction by hydrogen. Methane, benzene and camphor were used to produce CNTs at 600, 700, 800, 900 and 1000 °C. The results show that the types of carbon precursors greatly affect the quality of CNTs produced. The CNTs obtained from the decomposition of methane had the lowest intensity of D band to G band ratio (ID/IG) compared to the ID/IG ratios of CNTs produced using benzene and camphor at 900 and 1000 °C, respectively. This low ID/IG ratio is due to the difference in the molecule structures between methane, benzene and camphor, which resulted in different CNT growth mechanism. Raman analysis showed that single-walled carbon nanotubes of high quality were formed at 900 °C using methane as carbon precursor.