The Preparation And Catalytic Performance Research For Nanocatalysis Composites Based On Brookite TiO₂

Titanium dioxide has been a hot material of photocatalytic field due to its high activity, stability, non-toxic and cheap, etc. However, the preparation of phase-selected titania nanocrystals has still remained challenging to now, owing to the formation of designated crystalline structure is intensely mediated by various complicated thermodynamic and kinetic factors. Particularly, the narrower stability region of brookite as compared to anatase and rutile counterparts, the acquisition of exclusive brookite phase is extremely tough and it was frequently produced as a minor byproduct in the resulting samples. The main results are summarized as follows:(1) Brookite TiO2similar nanorod structure was synthesized through a solution chemistry route. The growth process of brookite TiO2was obtained by adjusting systematically variables of reaction temperature and duration. Detailed experimental characterizations and photocatalytic performances measures indicated that brookite showed special structure and photocatalytic activity. In addition, we also studied the effects of titanium source and the polarity of solvent on the formation and photocatalytic properties of brookite TiO2.(2) Cu doped brookite TiO2was first composed by hydrothermal-calcination method. The phase structure was easily destroyed when transition metal Fe、Cd、Ni doped though some methods. But Cu doped brookite TiO2can be synthesized by hydrothermal-calcination method which was increased the amount of urea. Further, the Cu doped brookite TiO2showed a photocatalytic activity under visible light.(3) ZnO2/brookite HO2heterostructure was constructed through two-step hydrothermal-photodeposition method. Brookite TiO2nanorod with specific exposed surface by urea modified hydrothermal method was first compounded. Afterwards, the broad gap semiconductor material-ZnO2was deposited on the {210} plane of the nanorod by using the strong oxidation of brookite {201} surface. Moreover, based on exploring the exiting features and the bandstructure match between ZnO2and brookite under UV light irradiation, reasonable catalytic mechanisms were proposed.