Preparation Of PEO Photocatalyst Film On Titanium Substrate

In this work,TiO₂ photocatalytic films were prepared by the method of plasma electrolytic oxidation and the combination of impregnation and calcination,and the properties of the post-treatment TiO₂ film were studied.The reuse performance of TiO₂ photocatalytic films was also studied.The results showed that the surface morphology of the post-treatment TiO₂ film has changed significantly.It was found that the film treated by impregnation and calcinations was relative rough and the specific surface area increased significantly.With the increase of H2SO4 concentration,the grains changed from cubic to layered shape.The grains became regular cubic shape with the increase of immersion time.The grains changed from the cubic particles to the strip shape,and then became rice-shaped when the calcination time was extended.As the calcination temperature increased,the surface of the film was covered with cubic particles.The Ti O2 film treated by impregnation and calcinations was mainly composed of anatase and rutile phase TiO₂.The effect of sulfuric acid concentration and calcination temperature on the composition of crystalline phase is larger.With the increase of the concentration of sulfuric acid,the content of anatase and rutile phase TiO₂ first increased and then decreased.With the increase of calcination temperature,the intensity of TiO₂ diffraction peak of rutile and anatase phase gradually enhanced.Under the optimum experimental conditions,the film is covered by cubic grains,and the specific surface area is large,the content of rutile and anatase TiO₂ is high.The TiO₂ photocatalytic films were used as catalysts.The photocatalytic activity of film was determined by degrading aqueous solutions of methylene blue.The photocatalytic degradation effect of the film without being post-treatment was only 62.4%,while the film treated with 750? exhibited the highest photocatalytic activity for degradation of MB,the photocatalytic degradation could reach 93.1%,the catalytic effect was increased by 30.7%.Under the optimum experimental conditions,the catalytic effect is 92.4%,the catalytic effect was increased by 30.0%.It indicated that the photocatalytic activities of the films improved significantly after impregnation and calcinations.We also investigated the reusability of the TiO₂ photocatalytic films.The best photocatalyst was used to do the repeated experiment.The result showed that the Ti O2 photocatalytic film exhibited a good reusability when used as a catalyst.