The Research On The Photocatalysis Properties Of TiO₂/Al₂O₃ Composite Films

TiO₂ is a cheap, high activities, safe and non-pollution semiconductor material. It is widely used in insulation, photocatalytic materials, reflection reducer, oxide sensors, humidity sensors and electro-colored windows. It has an extent applied expect because of its photocatalitic properties.This dissertation studied on the preparation of TiO₂/Al₂O₃ composite films and their photocatalytic properties. The technique of the electrochemical anodization was employed to synthesize anodic aluminum oxide films. TiO₂ film was successfully fabricated by alternating electrodeposition in the titanic solution, and its physical properties were studied. Various measurements including SEM, XRD and DRS were used to characterize the morphology, structure, composition. Photocatalysis of TiO₂/Al₂O₃ composite films in the anatase form was studied for the photocatalytic degradation of methyl orange solution .We have researched the influence of the preparation condition of TiO₂/Al₂O₃ on the photocatalisis properties of films. In the TiO₂/Al₂O₃ composite film, we deposited silver to compose TiO₂,Ag/Al₂O₃ composite film and improve its photocatalisis properties, and analyzed it in the abstract. AC impedance spectra of TiO₂/Al₂O₃ and TiO₂,Ag/Al₂O₃ was tested. The main results and conclusion can be summarized as follows:1) TiO₂ was deposited in the alumina holes. And an optimal process was found to deposit this film;2) The oxidation time and hole-extension time of the alumina,TiO₂ deposit time and heat treatment had a certain effect on the photocatalitic properties of the TiO₂/Al₂O₃ composite films;3) The certain silver ion deposited in the TiO₂/Al₂O₃ composite films to prepare TiO₂,Ag/Al₂O₃ films and improve the photocatalitic properties;4) Under the different lamp irradiation, the photocatalitic properties of composite films TiO₂/Al₂O₃ were compared: ultraviolet sterilized lamp was the strongest, incandescence lamp was the weakest. And the photocatalitic properties of composite films TiO₂,Ag/Al₂O₃ were compared: Under incandescence lamp, improved the most, under ultraviolet sterilized lamp, improved the least;5) Results were discussed on the morphology, DRS and AC impedance diagram of the TiO₂ films.