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Investigation of single-walled carbon nanotube growth parameters using alcohol catalytic chemical vapour deposition

A detailed parametric study of single-walled carbon nanotubes (SWNTs) synthesized in powder form and on substrates using the alcohol catalytic chemical vapour deposition (ACCVD) method is reported. As-grown SWNTs were analysed using transmission electron microscopy (TEM), field-emission scanning electron microscopy (FE-SEM), Raman spectroscopy and UV–vis–NIR spectroscopy to obtain structural and electronic information. We found that nucleation and growth of SWNTs occurs within seconds after introduction of the alcohol vapour and that high quality SWNTs with a narrow diameter distribution without amorphous carbon can be grown using Co acetate catalyst doped with Fe acetate above 750 °C. Defective multiwalled nanotubes were observed at lower temperatures, with the optimum temperature being 850 °C. These and other results reported in this paper allow the basis for optimizing the ACCVD process for the synthesis of large numbers of SWNTs.