复合催化剂SiO_2/CNI的制备及其光催化性能研究

Study on preparation and photocatalytic performance of SiO_2/CNI composite catalyst

以碘化铵和二氰二胺为原料,采用水浴-锻烧法制备了SiO_2/碘氮化碳(CNI)复合光催化剂。利用透射电子显微镜(TEM)、紫外-可见漫反射光谱(UV-Vis DRS)等方法对催化剂进行了表征。以亚甲基蓝、甲基橙分别为光催化反应模型化合物,评价了SiO_2/CNI的可见光催化活性。研究结果表明,与纯CNI相比,CNI/SiO_2复合光催化剂具有更高的催化活性,当SiO_2与CNI的质量比为1∶15时,光催化剂的降解率达到最高点,在该优化条件下,可见光照射40min,SiO_2/CNI光催化降解亚甲基蓝的降解率达到66.8%,光催化降解甲基橙的降解率达到23.7%。

Using ammonium iodide and dicyanodiamine as the precursors respectively,SiO_2/CNI composite photocatalysts with different mass ratio of SiO_2 and CNI were successfully prepared by a bath-calcination process,and characterized by transmission electron microscopy（TEM）and UV-Vis diffuse reflection spectra（UV-Vis DRS）.The visible light catalytic activities of SiO_2/CNI were evaluated with methylene blue and methyl orange as photocatalytic reaction model compounds,respectively.The experimental results showed that the photocatalytic activity of samples was greatly enhanced which compared with pure CNI.When the mass ratio of SiO_2 and CNI was 1∶15,SiO_2/CNI activity was the highest.Under the optimization condition,irradiation of 40 min with visible light,photocatalytic degradation rates of methylene blue and methyl orange reached 66.8% and 23.7% respectively by SiO_2/CNI（1∶15）as the catalyst.