Low-Temperature Synthesis of Single-Walled Carbon Nanotubes in a High Vacuum Using Pt Catalyst in Alcohol Gas Source Method

The growth of single-walled carbon nanotubes (SWCNTs) was carried out on SiO2/Si substrates with Pt catalysts between 500 and 700 degrees C under various ethanol pressures using an alcohol gas source method in a high vacuum and the grown SWCNTs were characterized by scanning electron microscopy (SEM) and Raman spectroscopy. It was found that, irrespective of the growth temperature, the optimal ethanol pressures were 1 x 10(-3)-1 x 10(-4) Pa, which were much smaller than those used in the SWCNT growth with Co catalysts. SEM observations showed that the yield of SWCNTs grown with a Pt catalyst under 1 x 10(-3) Pa at 700 degrees C was similar to that with a Co catalyst under the optimal growth condition, even though the ethanol pressure was fairly lower in the growth with Pt. By optimizing the growth pressure, SWCNTs could be grown even at 500 degrees C by using a Pt catalyst. (C) 2012 The Japan Society of Applied Physics