论文部分内容阅读
在TiO2/聚苯乙烯复合材料表面沉积硫化银,空气中煅烧制备了Ag+/Ag修饰的二氧化钛纳米空心球(Ag+/Ag-TiO2纳米空心球,即Ag+/Ag-HTS)。结果表明,所制备的Ag+/Ag-HTS具有可见光催化降解甲基橙的活性,随着甲基橙的初始浓度降低其催化降解效率提高。肖特基势垒的形成有助于更多的空穴转移到材料的表面,增强其光催化效率;表面的Ag+有助于电子的清除,防止光激电子与光激空穴复合。随着硫化银沉积数量的提高,Ag+/Ag-HTS的可见光催化活性提高,其光催化降解甲基橙的反应具有假一级反应的动力学特征。使用25%Ag+/Ag-HTS光催化剂,在可见光下照射2 h甲基橙降解率高达70.6%。
Ag + / Ag modified titanium dioxide nanospheres (Ag + / Ag-TiO2 nanospheres, Ag + / Ag-HTS) were prepared by depositing silver sulfide on the surface of TiO2 / polystyrene composites and calcining in air. The results showed that the prepared Ag + / Ag-HTS possessed the activity of visible light photocatalytic degradation of methyl orange, and its catalytic degradation efficiency increased as the initial concentration of methyl orange decreased. The formation of Schottky barrier helps to transfer more holes to the surface of the material and enhance the photocatalytic efficiency. The Ag + on the surface helps to eliminate the electrons and prevent the photo-induced recombination with the photo-induced holes. With the increase of silver sulfide deposition, the visible light activity of Ag + / Ag-HTS increases, and its photocatalytic degradation of methyl orange has the pseudo-first-order kinetics. With 25% Ag + / Ag-HTS photocatalyst, methyl orange was degraded up to 70.6% under visible light irradiation for 2 h.