TiO2 films doped with ZnFe2O4 were prepared by a sol–gel method. The crystalline structure, photocatalytic efficiency and optical absorption band were investigated using X-ray diffraction and Ultraviolet-Visible spectrometer. The doping of ZnFe2O4 improves the photocatalytic efficiency and broadens the optical absorption band of TiO2 films. The photocatalytic efficiency of TiO2 films increases from 12 to 32% with the presence of ZnFe2O4. The exciting wavelength of TiO2 films shifts about 20 nm to the visible light regions when the molar ratio of ZnFe2O4 is 2%.
