Mass production of high-quality single-wall carbon nanotubes by H2-N2 arc discharge

High-crystalline single-wall carbon nanotubes (SWNTs) have been produced by dc arc discharge evaporation of carbon electrode including 1 at.% Fe catalyst in H2-N2 mixture gas. The yield of as-grown SWNTs reaches higher than 70 at.%, and the form of SWNTs takes like a huge web. Raman scattering studies suggest that the diameter distribution of SWNTs can be controlled by varying the mixing ratio of H2 and N2 gas. Moreover, we can easily remove the coexisting Fe catalyst nanoparticles and obtain purified SWNTs. This new method for producing gram order of quantities of high-quality SWNTs will accelerate the studies of physical properties and practical applications of bulky SWNTs.