磁载WO3－TiO2／SiO2／Fe3O4复合光催化剂的制备及其光催化活性

 用溶胶－凝胶法在表面包覆了SiO2的磁基体Fe3O4上负载TiO2,从而得到了易于磁性固液分离的磁载WO3－TiO2／SiO2／Fe3O4复合光催化剂,并通过IR,XRD,SEM和XPS等测试手段对催化剂进行了表征．研究了磁载WO3－TiO2／SiO2／Fe3O4复合光催化剂对亚甲基蓝溶液脱色的性能,并考察了WO3掺杂量对样品催化活性的影响．结果表明,n（WO3）／n（TiO2）＝0．001时,磁载WO3－TiO2／SiO2／Fe3O4复合光催化剂的催化活性最高,循环使用3次时脱色率仍保持在98％．

Preparation and Photocatalytic Activity of WO3-TiO2/SiO2/Fe3O4 Magnetite Photocatalyst

Photoassisted catalytic decomposition with some semiconductors has been a promising method for the elimination of organic pollutants in water and atmosphere. It has been shown that TiO 2 demonstrates the highest quantum yield among the popular semiconductors. However, the photocatalytic activity of TiO 2 is not high enough for industrial purposes. Our work is concerned with the enhanced setting and reuse of suspended photocatalysts. The photocatalysts combined with magnetite make them be recycled easily from the treated water by magnetic force without complicated equipment and further processing. In order to further improve the photocatalytic efficiency of TiO 2, several methods have been applied, such as increasing the external surface area of the photocatalysts, doping additives in TiO 2 and modifying the TiO 2 surface with metal or other semiconductors. Our aim in this work is to investigate the role of WO 3 in enhancing the photocatalytic activity of TiO 2. The magnetic photocatalyst WO 3 TiO 2/SiO 2/Fe 3O 4 has been successfully prepared by sol gel method with magnetite SiO 2/Fe 3O 4 as a matrix. The catalyst samples were characterized by IR, XRD, SEM and XPS, respectively. The photocatalytic activity of the catalysts was investigated by photocatalytic decolorization of methylene blue. The results indicated that the photocatalytic activity of the composite photocatalyst with n (WO 3) / n (TiO 2) =0 001 is higher than that of TiO 2/SiO 2/Fe 3O 4 and the photocatalytic efficiency still remains 98% after being reused for 3 times.