双晶型TiO_2薄膜的低温制备及表征

Low-temperature Preparation and Characterization of TiO_2 Thin Films with a Bicrystalline Framework

采用溶胶-凝胶法低温制备了具有锐钛矿、板钛矿双晶型的TiO2薄膜.分别利用X射线衍射(XRD)、透射电子显微镜(TEM)、UV-Vis透光率曲线和原子力显微镜(AFM)等手段对所得TiO2溶胶和薄膜进行了性能表征.采用光催化降解罗丹明B水溶液评价TiO2薄膜的光催化活性.结果发现,所得TiO2薄膜具有较高的透明度和光催化活性.同时,考察了溶胶回流温度对所制备TiO2薄膜性能的影响,发现升高溶胶回流温度可以完善薄膜的晶型,增大薄膜的粗糙度,从而提高薄膜的光催化活性.溶胶回流温度为100℃时所制备的TiO2薄膜具有最高的光催化活性.

TiO2 thin films were prepared at low-temperature by the sol-gel method. The as-prepared TiO2 sols were characterized with X-ray diffraction （XRD） and transmission electron microscopy （TEM）, TiO2 films were characterized with UV-Vis spectra and atomic force microscopy （AFM）, respectively. The photocatalytic activity of the thin films was evaluated by the degradation of rhodamine B in aqueous solution under UV irradiation.The results indicated that a bicrystalline framework of anatase and brookite was present in the as-prepared films. And the TiO2 films showed high transmittance and photocatalytic activity. The effect of sol-refluxing temperature on the performance of TiO2 films was investigated. The increase of sol-refluxing temperature led to the improved photocatalytic activity of TiO2 films. This is due to the crystaUine perfection of TiO2 sols and average roughness enlargement of TiO2 films. The TiO2 films prepared by the sol refluxed at 100℃ showed the highest photocatalytic activity.