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Micro-porous TiO2 ceramic films have been grown on titanium plates by the micro-plasma oxidation method with the electrolyte of H2SO4. The influence of La3+ ion addition in the electrolyte on the photo-catalytic activities was investigated. The results showed that titanium dioxide thin films produced with La3+ addition electrolyte exhibit higher photo-activity than pure electrolyte for the oxidation of rhodamine B. The removal of rhodamine B reaches 90% for 30 min when La3+ addition concentrate is 0.05 g/L. Experimental results of X-ray diffraction and atom force microscopy show that the increase in activity is related to change in the lattice parameters and cell volume.

The anodized TiO2 ceramic film was post-treated by photoreduction and ion sputtering, respectively, to deposit platinum on the surface of the films. Surface morphology, the main elements of the films and platinum distribution on the film surface were investigated by scanning electron microscopy and energy dispersive spectroscopy. The phase composition of the films was examined by X-ray diffraction. The photocatalytic activity was compared through the effect of the films on photocatalytic (PC) degradation rate of the humic acid. The results showed that both films were composed of Pt5Ti3, rutile (R) TiO2 and anatase (A) TiO2, and the content of TiO2 (R) of the film prepared by photoreduction was a little more than that of the film by ion sputtering. Compared with Pt on the Pt-TiO2 ceramic film by photoreduction, Pt on the Pt-TiO2 film by ion sputtering dispersed more evenly and the grains were much smaller. Pt particulates in the film post-treated by ion sputtering were more strongly combined with the film than those by photoreduction. Besides, the PC degradation rate of humic acid by both Pt-TiO2 films were higher than that by TiO2 film, and Pt-TiO2 film by ion sputtering had higher catalytic activity and longer using life than that by photoreduction.

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 TiO2 and anatase TiO2. The compound WO3-TiO2/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-TiO2/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 TiO2/Ti ceramic film.

With the approach of anodic oxidation, TiO2/Ti film doped with Cu2+ was produced in H2SO4 electrolyte mixed with CuSO4. The surface morphology and the roughness of the films were studied with atomic force microscopy. The phase composition of the films was studied by X-ray diffraction. The photocatalytic activity of the films was compared through the photocatalytic degradation rate of phenol. The relations of the photocatalytic activity to the concentration of Cu2+, the microstructure and the surface roughness of the film were investigated. The results showed that Cu2+ increased the surface roughness and restrained the growth of crystal. In addition, the phenol in aqueous solution was successfully photodegraded under visible light irradiation by Cu2+-TiO2/Ti film. The composition and structure of the film affected the catalytic activity greatly. Compared with TiO2/Ti film, the recombination rate of e- and h+ of Cu2+-TiO2/Ti film was decreased.