Covalent sidewall functionalization of single-walled carbon nanotubes via one-electron reduction of benzophenone by potassium

We reported a method for covalent sidewall functionalization of single-walled carbon nanotubes via one-electron reduction of benzophenone by potassium. The reaction of a potassium atom with a benzophenone molecule results in transferring one electron from the potassium to the benzophenone, forming a radical anion, which adds readily to nanotubes. Raman and UV-vis spectroscopy confirm unambiguously that covalent functionalization has taken place. ATR-FTIR spectroscopy shows that diphenylcarbinol groups have been grafted onto the sidewalls of nanotubes. The degree of functionalization was measured by thermogravimetric analysis (TGA). (C) 2007 Elsevier B.V. All rights reserved.