中文摘要：

通过液相沉积法制备了CeO2/g-C3N4复合光催化剂,利用X射线衍射、氮气吸脱附、紫外可见漫反射等方法对其进行了表征,考察了CeO2/g-C3N4复合光催化剂在可见光下降解罗丹明B的光催化活性,并对光催化反应机理进行了初步探讨.结果表明,复合光催化剂中g-C3N4和CeO2分别为石墨相和萤石相,其中存在堆积介孔结构,随着CeO2掺杂量的增加,CeO2/g-C3N4复合光催化剂的比表面积逐渐增大.CeO2掺杂提高了光生电子—空穴对的分离效率,使得CeO2/g-C3N4复合光催化剂的活性比单纯g-C3N4有所提升,其中CeO2掺杂量为6%的复合光催化剂活性最高,在可见光照射150 min后对罗丹明B染料的降解率可达94%.在复合光催化剂对罗丹明B的降解过程中,光生空穴是主要的活性物种.

英文摘要：

A metal-free g-C3N4 photocatalyst was prepared by calcination method, and the CeO2/ g-C3N4 composite photocatalysts were synthesized by deposition of CeO2. The samples were characterized by X-ray diffraction（ XRD）,nitrogen adsorption and UV-Vis diffuse reflectance spectroscopy（ DRS） techniques. The photocatalytic activity and mechanism of the CeO2 doped on g-C3N4 catalysts were tested in the degradation of Rhodamine B（ Rh B） under visible light irradiation. The results showed that the g-C3N4 was graphite phase and the CeO2 was fluorite phase in the composite photocatalysts,and the composites had mesoporous structure. The doping of CeO2 increased the surface area of the Ce O2/ g-C3N4 composite and improved the electron / hole separation efficiency. Compared with the pure g-C3N4,CeO2/ g-C3N4 showed higher photocatalytic activity,and the photodegradation rate of Rh B was 94% on the 6% CeO2/ g-C3N4 composite with visible light irradiation for 150 min. The photogenerated holes on the composite are the main active species in the photocatalytic degradation of Rh B.