Parametric study of nanotube growth from C2H2 and C60 on supported iron catalyst particles

Abstract

CVD growth of nanotubes from two carbon feedstock gases C2H2 and C60, is facilitated by correlating two important parameters: size distribution of catalytic iron particles and temperature. The thickness of catalytic iron films deposited on Si substrates was controlled between 0.5 and 20nm. The annealed iron films were imaged with atomic force microscopy showing the distribution of iron particles. It was found that with increasing film thickness, both the particle diameter and height increase. After this treatment of the Si substrates, nanotube growth was performed at various temperatures between 550°–1100°C. The mean nanotube diameters remain constant while the nanotube growth rate depends on temperature. The density of CNT formation is temperature dependent. The presence of SWNT was observed at high temperatures (850°–950°C). SEM, TEM and Raman spectroscopy were used for sample analysis.