Fe3+-TiO2/SiO2薄膜催化剂的结构对其光催化性能影响

以硅胶为载体,采用溶胶-凝胶法制备了掺杂不同量Fe3+的TiO2光催化剂(Fe3+-TiO2/SiO2),以氙灯为光源,罗丹明B为目标降解物,对其光催化活性进行了研究.结果表明,Fe3+-TiO2/SiO2比TiO2纳米粉有更好的催化活性,Fe3+的最佳掺入量为0.03％.罗丹明B在粉体和膜催化剂的作用下遵循不同的光催化反应机理.根据XRD,SEM,Raman,XPS和FTIR的表征结果可认为,TiO2在SIO2表面薄膜化和Ti-O-Si键的形成是催化活性提高和降解机理不同的主要原因.

Structure Influence of Fe3+ Doped TiO2/SiO2 Film on the Photocatalytic Properties

Fe3+ ion doped titanium dioxide films coated on silica(Fe3+-TiO2/SiO2) were prepared by sol-gel method. The obtained films were more effective than TiO2 nano-size powder in decomposing Rhodamine B under irridation with Xe lamp. In the Fe3+ doping system, the optimum value of the Fe3+/Ti4+ (atomic ratio ) was 0. 03 % for the photocatalytic degradation of Rhodamin B. The experimental results suggested that the photocatalytic reactions with the titanium dioxide nanosize powder and film as the catalyst proceed in two different degradation mechnisms. By the characterization using XRD, SEM, Raman, and FTIR technologies, we can conclude that the surface layer structure of TiO2 film on silica and the formation of Ti-O-Si bond play important roles with the increasing of degradation efficiency, and result in two different decomposition mechanisms for film and power.