Purification of single-walled carbon nanotubes synthesized by the hydrogenarc-discharge method

A simple procedure for the purification of the single-walled carbon nanotub e (SWNT) product synthesized by the hydrogen arc-discharge method was propo sed and discussed. The procedure involves ultrasonication in alcohol, oxida tion in fixed air, and soaking in hydrochloric acid. Most of the amorphous carbon and carbon nanoparticles as well as metal particles in the product w as successfully removed, according to the results obtained from transmissio n electron microscopy, thermogravimetric analysis, and resonant laser Raman measurements. With this procedure, a 41 wt% yield of the SWNTs with a puri ty of about 96% was achieved after purification.