Preparation, Characterization And Antibacterial Properties Of TiO₂ Based Nanocrystalline Composites

TiO₂ semiconductor photocatalyst has the function of sterilization, deodorization, antipollution and so on. As one of the purification materials of the new generation, it has been widely applicated for its high catalysis activeness, chemical stability, inexpensive and security. But its hyperthermophilic property is bad, which restricts the application and development in high temperature treatment and preparation craft, such as ceramics.In this article, series TiO₂ based nanocoposite powders were prepared by precipitation. The heat resistance, photocatalysis and antibacterial properties of TiO₂ were studied when it is composited by ZnO, SnO₂, Al₂O₃, SO₄^2-, Cr₂O₃ respectively.The phase transformation of TiO₂ could be remarkably promoted when compsited by ZnO or SnO₂. When calcined, TiO₂ and ZnO produce ZnTiO₃ which has a similar structure of rutile, while SnO₂ has rutile structure. So composited heterogeneous compound with the structure of rutile, the phase transformation of TiO₂ could be promoted when calcined under low temperature.For the reason of the similar structure of Al₂O₃, SO₄^2- and anatase, the hyperthermophilic property of TiO₂ was enhanced enormously after composited by Al₂O₃ or compsited by Al₂O₃ and doped with SO₄^2-. Calcined from 950℃ to 1050℃, Al₂O₃/TiO₂ nanocomposites were the mixture crystal of anatase and rutile, and the content of anatase was about 80% to 20%. When Al₂O₃/TiO₂ nanocomposites doped with SO₄^2-, the mixture crystal of anatase and rutile could be got at the calcined temperature from 1050 ℃ to 1150 ℃; the size of TiO₂ nanocoposite particle was...