AgBr/Ag_3PO_4的制备、表征及光催化性能研究

Preparation,characterization and photocatalytic performance of AgBr/Ag_3PO_4

采用沉淀置换法制备了表面沉积AgBr的复合催化剂AgBr/Ag3PO4,并利用SEM、XRD和UV-Vis等方法对其进行了表征。以难降解有机染料甲基橙(MO)为模型降解物,考察了其可见光催化降解性能和循环利用性。结果表明:复合材料对可见光的响应范围增大,在波长大于500nm的可见光区,AgBr/Ag3PO4的吸收强度大于Ag3PO4。可见光照射60min,复合前后催化剂对MO的降解率分别为33.30%和96.01%。在优化的催化条件下,复合催化剂20min对MO降解率为94.19%。复合前后催化剂溶解性差异及复合催化剂中光生电子-空穴对更好的传输和分离是催化剂性能提高的重要原因,该材料具有较好的稳定性,可重复使用。

The composite photocatalyst AgBr/Ag3PO4 with AgBr depositionon on the surface was prepared by precipitation replacement method and characterized by means of SEM,XRD and UV-Vis spectrophotometry.Photocatalytic activity and reusability of the catalyst were studied under a visible light source with persistent organic dyes as model pollutant.Results showed that the composite had wider response range of visible light and the absorption intensity was higher than Ag3PO4 under visible-light region of wavelength over 500 nm.Degradation rates for MO of the catalyst before and after compositing were 33.30% and 96.01%respectively under 60 min irradiation of visible light.Under optimized catalytic conditions,degradation rate of catalyst was 94.19%in 20 min.Solubility difference of the catalyst before and after compositing and effective transmission and separation of photoexcited electron-hole pairs of the catalyst were main reasons of performance improvement.This material was quite stable and can use repeatedly.