High yield of single-wall carbon nanotubes by arc discharge using Rh–Pt mixed catalysts

Single-walled carbon nanotubes (SWNT) were produced using binary mixtures of the platinum-group metals as catalysts by arc evaporation in helium gas. Transmission electron microscopy and Raman scattering spectroscopy revealed that the production yield of SWNTs was remarkably enhanced when a Rh–Pt mixture was used as a catalyst. The density of SWNTs in raw soot was as high as that obtained from Fe–Ni and Y–Ni. The distribution of diameters of SWNTs was narrow (1.28±0.07 nm). The merit of this catalyst is that it is free from magnetic metals.