SET mechanism in the functionalization of single-walled carbon nanotubes

Dispersions of carbon nanotube salts prepared by treating single-walled carbon nanotubes (SWNTs) with lithium in liquid ammonia react with aryl and alkyl sulfides by single electron transfer (SET) to yield transient radical anions that dissociate into carbon-centered free radicals and mercaptide. The free radicals add to the sidewalls of the nanotubes or recombine with SWNT radical anions. AFM images indicate that the derivatized SWNTs are partially debundled. Disulfides react.with carbon nanotube salts to yield SWNTs functionalized by sulfur-centered radicals.