以商业锐钛矿TiO:和钼酸铵水溶液作为前驱体,利用浸渍一焙烧的方法制备了MoO,与TiO:不同质量比率的MoO3/TiO2复合光催化剂。采用x射线衍射、高分辨透射电镜和紫外.可见漫反射对其进行了表征。以甲基橙为光催化反应的模型化合物,评价了其紫外光催化活性和MoO3/TiO2复合光催化剂的紫外产氢活性。通过添加各种自由基清除剂研究了甲基橙在光催化反应过程中的活性物种。结果表明:与纯的MoO3和TiO2相比,20%MoO3/TiO2光催化剂在400一700nm区域具有更强的光吸收性能并且吸收带边向长波方向移动。在所有MoO,/TiO,样品中,20%MoO3/TiO2光催化剂具有最高的紫外光活性。·OH,h‘,·0i和H2O3,特别是h,共同支配了甲基橙的光催化降解过程。
Using commercial anatase TiO2 and an aqueous solution of (NH4 )6Mo7024 4H20 as precursors, MoO3/TiO2 composite photocatalysts with different mass ratios of MoO3 and TiO2 were prepared by impregnation-calcination method. The obtained samples were characterized by X-ray diffraction(XRD), high-resolution transmission electron microscopy (HRTEM) and UV-visible diffuse reflectance (UV-Vis DRS). The UV light photocatalytic activity of MoO3/TiO2 was evaluated using methyl orange(MO) as model compounds. Furthermore, the UV light photocatalytic activity of H2 evolution on MoO3/TiO2 composite photocatalysts was also evaluated. The active species in the photocatalytic reaction process of MO were studied by adding various radical scavengers. The results indicate that compared with pure MoO3 and TiO2, 20% MoO3/TiO2 photocatalyst in the 400-700 nm region has a stronger optical absorption property and the absorption band edge moves to longer wavelengths. In all MoO3/TiO2 samples, 20% MoO3/TiO2 photocatalyst has the highest UV light photocatalytic activity. OH, h , O and H202, especially h + together dominated the photocatalytic degradation process of methyl orange.