TiO_2/SiO_2复合薄膜的结构表征及光学特性研究

Structure and Optical Properties of TiO_2/SiO_2 Composite Films

利用Sol-Gel二步水解法制备了TiO_2/SiO_2复合薄膜材料,对样品在空气气氛中进行加热,再于不同温度下进行了退火处理。采用XRD以及Raman谱表征了样品的微结构,并通过紫外可见透射谱研究了样品的光学特性。结果表明,样品的光学特性与样品中SiO_2含量存在依赖关系,并分析了相应机理。

TiO2/SiO2 composite films were fabricated by the sol-gel method, which was followed by preheating the products in air and annealing at different temperatures. The structures of the film was analyzed by X-ray diffraction （XRD） and Raman spectroscopy. The optical properties of samples were studied by UV-transmission spectroscopy and refraction indexes. Results showed that the grains in films was small in size. The absorption edge blue-shifted and the optical band gap broadened. These effects became more pronounced with the increasing contents of SiO2 in the films. All these effects were caused by the quantum confinement effects from the nanosize of crystallines.