Nitrogen-doped nano-TiO₂ ceramic film: Fabrication and application to photocatalysis

Owing to the defects of the fixed TiO₂ photocatalysts, the research employed the approach of anodic oxidation to produce high efficiend N-TiO₂/Ti ceramic film oxidized on the surface of titanium, in order to make the absorbable spectrum of light catalyst spread to the visible region and constrain the high recombination rate of electron-hole pairs during photoreaction. The surface appearance and the distribution of elements have been checked with scanning electron microscopy and EPMA. The microcrystal structure of the films has been checked with XRD. The results showed that the main components of nitrogen-doped catalyzer were rutile and anatase, meanwhile, the nitrogen element distributing on the film was fairly uniform. Films of N-TiO₂ photocatalysis reduction K₂CrO₄ revealed that with the amount of N-contained increased, the rate of reduction K ₂CrO₄ decreased under ultraviolet light while that increased under visible light. It was found that the highest reduction rate of K₂CrO₄ was achieved through an optimal (NH ₄)₂S₂O₈ dosage of 0.4g/L in ceramic film prepared processes.