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以钛酸丁酯、硝酸铋和硫脲为原料,采用溶胶-凝胶法制备了不同n[Bi(S)]/n(Ti)的Bi、S共掺杂的TiO2光催化剂。采用透射电子显微镜(TEM)、扫描电子显微镜(SEM)、X射线粉末衍射(XRD)、X射线光电子能谱(XPS)、激光拉曼光谱(FT-Raman)、紫外-可见漫反射吸收光谱(UV/vis DRS)、微反等方法对光催化材料进行了研究。结果显示,Bi、S元素在TiO2纳米颗粒中分别以Bi2O3和SO42-形式存在,共掺杂未能改变TiO2的锐钛矿结构。Bi掺杂后,通过形成Bi—O—Ti键在TiO2禁带中产生了杂质能级,降低了纳米材料的禁带宽度,从而提高了光吸收效率;而S的引入,增多了催化剂表面的酸性位,有利于光催化活性的提高。Bi、S掺杂能明显改善TiO2纳米颗粒光催化甘油水溶液制氢的性能,3%Bi、S共掺杂TiO2具有最高的产氢速率,在紫外光和模拟太阳光照射下,其产氢速率可分别达到1 514.9和190.2μmol/(h·g)。
Bi, S co-doped TiO2 photocatalysts with different n [Bi (S)] / n (Ti) were prepared by sol-gel method using butyl titanate, bismuth nitrate and thiourea as raw materials. The microstructure and mechanical properties were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), laser Raman spectroscopy (FT-Raman) UV / vis DRS), micro-reverse and other methods of photocatalytic materials were studied. The results show that Bi and S elements exist in the form of Bi2O3 and SO42- respectively in the TiO2 nanoparticles. Co-doping does not change the anatase structure of TiO2. After Bi doping, the impurity energy level is generated in the forbidden band of the TiO2 by Bi-O-Ti bond formation, which decreases the forbidden band width of the nanomaterials and improves the light absorption efficiency. However, the introduction of S increases the surface energy of the Acidic position, is conducive to the improvement of photocatalytic activity. Bi and S doping can obviously improve the performance of TiO2 nano-particles in the photocatalytic glycerol aqueous solution. The 3% Bi and S co-doped TiO2 has the highest hydrogen production rate. Under the ultraviolet and simulated sunlight, the hydrogen production rate Respectively up to 1 514.9 and 190.2 μmol / (h · g).