An easy approach to hydroxyethylated SWNTs and the high thermal stability of the inner grafted hydroxyethyl groups

A new approach to hydroxyethylated single-walled carbon nanotubes (SWNTs) is reported. Treating SWNTs with sec-butyllithium and subsequently with epoxy ethane leads to SWNTs functionalized with both butyl and hydroxyethyl groups. The functionalized SWNTs were characterized by Raman and FT-IR spectroscopy, thermogravimetric analysis (TGA) and atomic force microscopy. The degree of hydroxylation was estimated to be at least one hydroxyl group for every 31 nanotube carbon atoms from the TGA data and the resultant SWNTs can be stably dispersed in water at a concentration of 0.5 mg ml(-1). It was also found that the functional groups encapsulated in the channels of SWNTs possess a high thermal stability during the TGA procedure.