Preparation and photocatalytic property of WO₃-TiO₂ /Ti ceramic film via anodic oxidation treatment

The high efficient WO₃-TiO₂/Ti ceramic film was prepared on the surface of titanium by the approach of anodic oxidation in order to make the absorbable spectrum of catalyst spread to the visible region and restrain the high recombination rate of electron-hole pairs during photoreaction. The surface morphology and the distribution of elements were studied with scanning electron microscopy and energy dispersive spectroscopy. The phase composition of the films was investigated with XRD. The results showed that the main components in the coating were WO₃, rutile TiO ₂ and anatase TiO₂. The compound WO₃-TiO ₂/Ti ceramic film enlarged the range of the reacting visible light and increased the absorbing intensity. The rhodamine B was successfully photodegraded under visible light irradiation by WO₃-TiO ₂/Ti catalyst films. It was found that the highest degradation rate of rhodamine B was achieved through an optimal W dosage of 4.2 %(wt %) in WO₃-TiO₂/Ti ceramic film. It was also confirmed that the recombination rate of electron-hole pairs in WO₃-TiO₂/Ti ceramic film declined due to the existence of WO₃ in TiO ₂/Ti ceramic film.