硫和银共掺杂介孔TiO2的制备、表征及其对染料的光催化降解活性

以P123为模板，以钛酸四正丁酯、硝酸银和硫脲为原料采用模板法制备了一系列硫和银共掺杂介孔TiO₂光催化材料．利用SEM、XRD、BET和紫外-可见光谱等技术对其形貌、晶体结构及表面结构、光吸收特性等进行了表征．以甲基橙溶液的光催化降解为模型反应，考察了不同掺杂量的样品在紫外和可见光下的光催化性能．结果表明，用模板法制备的共掺杂介孔TiO₂光催化材料在紫外和可见光条件下较纯介孔TiO₂和单掺杂介孔TiO₂对甲基橙溶液具有更好的光催化降解效果, 且硫和银的掺杂量及样品焙烧温度显著影响该材料的催化性能．当硫掺杂量为2mol%和银掺杂量为1mol%，在500 oC 焙烧2 h所得光催化材料的催化性能最佳，4 h即可使甲基橙的降解率达98.8%，重复使用4次仍可使甲基橙的降解率保持在87.5%以上

Preparation, characterization of sulfur, silver co-doped mesoporous titania photocatalysts and their photocatalytic activity for dye decomposition

In order to improve the photocatalytic performance of mesoporous titania under visible light, a series of photocatalysts of S and Ag co-doped mesoporous titania have been successfully prepared by template method using thiourea, AgNO₃ and tetrabutyl titanate as precur-sors and Pluronic P123 (EO₂₀PO70EO20) as template. Scanning electron microscopy, X-ray diffraction, nitrogen adsorption-desorption measurements, and UV-visible spectroscopy were employed to characterize the morphology, crystal structure, surface structure, and optical absorption properties of the samples. The microcrystal of the photocatalysts consisted of anatase phase and was approximately present in the form of spherical particle. The photo-catalytic performance was studied by photodegradation methyl orange in water under UV and visible light irradiation. The calcination temperature and the doping content influenced the photoactivity. In addition, the possibility of cyclic usage of co-doped mesoporous titania was also confirmed, the photocatalytic activity of mesoporous titania remained above 89% of the fresh sample after being used four times. It was shown that the co-doped mesoporous titania could be activated by visible light and could thus be potentially applied for the treat-ment of water contaminated by organic pollutants. The synergistic effect of sulfur and silver co-doping played an important role in improving the photocatalytic activity.