采用水热法对介孔水合TiO2光催化剂进行掺铁改性;通过静态氮吸附、X射线衍射、透射电镜、紫外-可见吸收和X射线光电子能谱等手段对掺杂产物进行了表征;以氙灯为可见光源,以亚甲基蓝为目标物研究分析了掺铁产物的光催化活性。结果表明:铁以Fe3+掺入介孔水合TiO2中,铁的掺入虽然会抑制介孔水合TiO2晶粒的生长而减小其比表面积和介孔体积,但能明显地提高介孔水合TiO2在可见光照射下的光催化活性;催化活性提高的重要原因是掺铁会使其光吸收阀值降低而增加可见光的吸收;当掺铁量为0.69%(Fe/Ti摩尔比n)时催化活性最高,其对亚甲基蓝的降解效率是未掺铁产物的1.5倍,光催化循环4次后的降解率仍大于80%。
Fe-doped mesoporous TiO2 were prepared by one-step hydrothermal method.The Fe-doped samples were characterized by nitrongen-adsorption,X-ray diffraction (XRD),transmission electron microscopy (TEM),UV-Vis spectrophotometer and X-ray photoelectron spectroscopy (XPS).Their photocatalytic activities were evaluated by using methylene blue (MB) as model pollutant under xenon lamp.The results indicated that the doped Fe reduced specific surface area and mesoporous volume of the Fe-doped sample,while it can broaden the light response range of the Fe-doped sample,enabling the light absorption threshold (λg) of the typical Fe-doped sample increase to 441 nm from the lower 406 nm of the undoped sample,and thus increased the photocatalytic activities under visible light irradition.In addition,the results showed that the typical Fe-doped sample with Fe/Ti molar ratio of 0.69% presented the highest photocatalytic activity to MB.After 4 cycles of photocatalytic degradation to MB,the Fe-doped sample presented a small loss of the photocatalytic activity.
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