三维有序大孔复合材料Ag/ZnO-TiO_2的制备及微波辅助光催化性能

Preparation of 3DOM Periodic Composite Ag/ZnO-TiO_2 and Microwave-assisted Photocatalytic Performance

采用聚苯乙烯(PS)微球作为模板剂,经溶胶-凝胶及煅烧后处理等方法制备了三维有序大孔复合材料Ag/ZnO-TiO2.通过傅里叶变换红外光谱(FTIR)、X射线衍射(XRD)、X射线光电子能谱(XPS)、N2吸附-脱附和扫描电子显微镜配合X射线能量色散谱(SEM-EDS)等手段对其组成、结构及形貌等进行了表征.结果表明,经PS微球处理后的Ag/ZnO-TiO2具有锐钛矿晶型结构,Ag以单质形式存在.该复合材料的孔结构排列整齐有序,孔壁为介孔结构,粒子堆积致密,平均孔直径约为150 nm,属于三维有序大孔材料(3DOM).在微波辅助光催化降解甲基橙等染料的研究中,该复合材料表现出较好的光催化性能,其活性明显高于商用光催化剂(Degussa P-25)等单体以及ZnO-TiO2二元体系.

Three-dimensionally ordered macroporous（3DOM） composite Ag/ZnO-TiO2 was prepared by the sol-gel method combined with a polystyrene（PS） latex sphere templating technique and calcination.The phase structures,chemical composition,optical absorption properties and surface physicochemical properties were characterized via Fourier transform infrared（FTIR） spectrum,X-ray diffraction（XRD）,X-ray photoelectron spectroscopy（XPS）,Transmission electron microscopy（TEM）,N2 adsorption-desorption tests and scanning electron microscopy assisted X-ray energy dispersive spectroscopy（SEM-EDS）.The results showed that the produced composite Ag/ZnO-TiO2,had anatase crystalline structure,well distribution,good structure and the silver species in the Ag/ZnO-TiO2 was metallic Ag.Moreover,the walls structure of the 3DOM Ag/ZnO-TiO2 was mesoporous with compact walls,and the average pore diameters were ca.150 nm.The photocatalytic activities of Ag/ZnO-TiO2 were tested by microwave assisted photocatalytic degradation of the dyes,for example,methyl orange.Results showed that this composite material had fine photocatalytic activities for many dyes,and the activity was higher than that of P-25 and binary system ZnO-TiO2.