Synthesis and purification of single-walled carbon nanotubes by AC arc discharge

Single-walled carbon nanotubes (SWNTs) were synthesized in a mixed gas of H-2 and Ar by AC arc discharge. The catalyst used in the synthesis was a single Fe catalyst. SWNTs containing a negligible number of nanoparticles were obtained. A novel purification method, in which synthesized soot is heated and oxidized in situ, was adopted. As a result, high-quality SWNTs with excellent crystallinity containing very few coexisting nanoparticles and fine particles from the catalyst were obtained.