Cr-doped TiO2 thin films deposited by RF-sputtering

Cr-doped TiO2 thin films with different band gaps were prepared. Higher Cr doping was beneficial to the formation of the rutile-TiO2 phase over the anatase-TiO2 phase. A 4.8% Cr-doped thin film indicated a band gap of 2.95 eV, which was lower than the band gap of the rutile-TiO2. Cr doping was accompanied by the formation of not only the rutile-TiO2 phase but also the Cr2O3 phase, lead to the degradation of the hydrophilicity. The TiO2 thin films with the mixed phase were not desirable to improve the hydrophilicity. (C) 2010 Elsevier By. All rights reserved.