Abstract
Purification of single-walled carbon nanotubes (SWNTs) is still remaining a challenging task. The aim of this work is to show novel and fast concepts for the purification of CNTs by combination of different techniques. The carbonaceous particles were presumably etched away by the selective oxidation with faster etching rate than nanotubes. This gives rise to very high yield of about 35%. It was found from Raman scattering measurements that the ratio of the intensity of G-line peak to that of D-line peak increased drastically by this purification process. The D-G ratio of dynamically air oxidized SWNTs (0.06) is much smaller than that of as-received (0.09) or air-HCl purified (0.1) SWNTs, indicating higher purity (and lower level of structural defects) of the dynamically air oxidized sample.