BiOI-sensitized nano-anatase (TiO2 (A)) photocatalysts were prepared by a deposition method at room temperature,and characterized by X-ray diffraction (XRD),X-ray photoelectron spectroscopy (XPS),and photoluminescence (PL),and UV-Vis diffuse reflectance spectra (UV-Vis DRS).The photocatalytic activities were evaluated by photo-degradation experiments of rhodamine B.With increasing BiOl content,the absorption intensity of BiOl/TiO2 (A) increases in the 370-630 nm region and the absorption band edge redshifts.The UV and visible light photocatalytic activities increase,reaching a maximum when the Bi/Ti molar ratio is 1.7％.The 1.7％ BiOl/TiO2 (A) catalyst exhibits much higher visible-light photoactivity than P25,and its UV-light photoactivity is slightly higher than that of P25.The UV and visible light photocatalytic activities of BiOl/TiO2 (A) with similar BiOl content are lower than those of BiOl/P25 catalysts.Compared with TiO2 (A),1.7％ BiOl/TiO2 (A) shows higher UV and visible light photoactivities.This is attributed to the strong absorption in the 370-630 nm region,the redshift of the absorption band edge,and the effective transfer of the photogenerated electrons and holes,which reduces the recombination of electron-hole pairs.%在室温条件下通过沉积法制备了BiOl敏化纳米锐钛矿TiO2(A)光催化剂.用X射线衍射(XRD),X射线光电子能谱(XPS),光致发光(PL)光谱和紫外-可见漫反射光谱(UV-Vis DRS)等手段对其进行了表征.通过罗丹明B (RhB)催化降解实验评价了其光催化活性.随BiOl含量增加,BiOl/TiO2(A)在370-630 nm的吸收强度增强,吸收带边红移增加,紫外和可见光催化活性先增加,当Bi/Ti摩尔比约为1.7％时,各自达到最大值,然后随BiOl含量的进一步增加而减小.1.7％ BiOl/TiO2(A)的可见光活性明显高于P25,它的紫外光活性也略高于P25.在BiOl含量相近时,BiOl/TiO2(A)比BiOl/P25具有更低的光催化活性,和TiO2(A)相比,1.7％ BiOl/TiO2(A)明显其有更高的紫外和可见光催化活性,这归因于它在370-630 nm的强吸收、吸收带边红移明显以及光生电子和空穴的有效转移,减少了电子-空穴对的复合.
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