CdS and S6+-modified TiO2 nanotubes were prepared to enhance the visible light activity of TiO2. The S6+ doping narrowed the band gap of TiO2 and increased the visible light response. Moreover, the S6+ doping decreased the standard reduction potential of the conduction band electrons to enhance the electron transfer of conduction band electrons from CdS to TiO2. CdS/S-TiO2 showed the higher activity as compared with CdS/TiO2 or S-TiO2, which was attributed to the synergetic effect between CdS and S6+ modification. (C) 2008 Elsevier B.V. All rights reserved.