Preparation and visible light catalytic activity of three-dimensional ordered macroporous CdS/TiO2 films

Abstract

A three-dimensional ordered macroporous CdS/TiO2 film was prepared by the sol-gel method with a colloidal crystal template and S2− ion exchange, and it exhibited high visible light photocatalytic activity for the aqueous degradation of rhodamine B and 4-chlorophenol. The modification with CdS gave visible light absorption by photosensitization and better separation of photo-induced electrons and holes. The ordered macroporous structure gave higher light utilization and faster reactant transport. 采用胶体晶体模板辅助溶胶-凝胶法以及S2–离子交换法合成了三维有序大孔CdS/TiO2膜. 结果表明, 该薄膜材料在可见光催化降解污染水中罗丹明B和对氯苯酚的反应中表现出高活性. 这可归因于修饰剂CdS的光敏化作用实现可见光催化, CdS-TiO2之间形成了异质结, 促进了电子和空穴的分离; 另一方面, 有序大孔结构有利于光的利用以及反应物的扩散和吸附.