Ultralong single-wall carbon nanotubes

The synthesis of 4-cm--long individual single-wall carbon nanotubes (SWNT) at a high growth rate of 11 μm s^-1 by catalytic chemical vapor deposition was discussed. The synthesis of a 4-cm-long individual SWNTs on a Si substrate indicates the possibility of synthesizing continuous SWNT without any length limitation. It was shown that the parameters that could be optimized for growing longer SWNTs include the flow rate and composition of the carrier gas, the growth temperature and the initial concentration of the catalyst solution. The Raman spectra and images of SWNTs were obtained with a Kaiser Optical confocal imaging Raman microscope.