利用吸附相反应技术制备得到了掺杂不同浓度的Fe2O3的TiO2复合光催化剂.通过透射电子显微镜(TEM)、紫外可见光谱和X射线衍射(XRD)研究不同掺杂浓度对TiO2形貌和结晶过程的影响,并利用3种波长光源下的甲基橙光降解实验考评了各个复合光催化剂的催化活性.结果表明,掺杂后复合光催化剂中Fe2O3分散性较好较均匀.在TiO2紫外可见吸收光谱中由于Fe2O3的掺杂而出现了红移,而且随着掺杂浓度增加红移越来越明显,复合光催化剂的禁带宽度也越来越小.在焙烧过程中无定形Fe2O3或Fe3+进入了TiO2的晶格结构,从而抑制了TiO2的结晶过程.半导体禁带宽度的减少以及TiO2结晶过程的抑制作用,都导致紫外光下复合光催化剂催化活性的降低.但Fe2O3的掺杂也使得复合光催化剂在可见光区出现了一定的光催化活性.%TiO2 photocatalysts doped with Fe2O3 were prepared by adsorption phase synthesis (APS). The influence of Fe2O3 concentration on morphology and crystallization of TiO2 was explored by TEM, UV-Vis and XRD. The activities of these photocatalysts were evaluated by photodegradation of methyl-orange irradiated under three wavelengths of light. The results suggest that the distribution of Fe2O3 in composite photocatalysts is homogeneous. Red shifts appear in UV-Vis absorpion of TiO2 after Fe2O3 doping and the red shift becomes obvious with increasing, in concentration of Fe2O3 , thus leading to decrease in the band gap of composite photocatalysts. Due to the entry of amorphous Fe2O3 or Fe3+ into lattice structure of TiO2, the crystallization of TiO2 is restricted. Both the decrease of band gap and the restriction on TiO2 doped with Fe2O3 would depress the activity of photocatalysts when irradiated at two wavelengths of UV light. However, Fe2O3 doping also leads to a certain activity of photocatalysts under visible light.
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