Preparation and characterization of hydroxylated multi-walled carbon nanotubes

The multi-walled carbon nanotubes (MWCNTs) were treated with four wet chemical oxidants (Na2ZnO2, Na3BO3, NaAlO2, NaOH) in order to prepare MWCNTs modified with hydroxyl groups. The resulting products were characterized with elemental analysis, Fourier transform infrared spectroscopy, thermogravimetric analysis, Raman spectroscopy and X-ray photoelectron spectroscopy. These results demonstrate that there are hydroxyl groups on the surface of treated MWCNTs while their structures are retained. The dispersions of untreated and treated MWCNTs indicate that treated MWCNTs can disperse more readily in chloroform than untreated MWCNTs. The concentration of hydroxyl groups of MWCNTs treated by NaAlO2 is the largest in four treated MWCNTs.