Surface modification of TiO2 nanoparticles with a C60 derivative and enhanced photocatalytic activity for the reduction of aqueous Cr(VI) ions

The surface of TiO2 nanoparticles (Degussa P25) was modified with a C60 derivative, C60(CHCOOH)2. In comparison to the pure P25, the modified TiO2 nanoparticles displays a higher photocatalytic activity with 97% of photocatalytic reduction efficiency of Cr(VI) ions after 1.5 h UV irradiation. In order to investigate the effect of the C60 derivative on the photocatalytic activity of the TiO2 nanoparticles, diffuse reflectance UV–vis spectra and photoluminescence spectra were measured. The results indicated that the enhanced photocatalytic activity of TiO2 nanoparticles may be ascribed to the enhancement of the photogenerated electron–hole separation because of the modification of the C60 derivative.