炭气凝胶孔结构对其负载的TiO_2光催化降解甲基橙性能的影响  

Influence of Carbon Aerogel (CA) Pore Structure on Photodegradation of Methyl Orange over TiO_2/CA

作　　者：崔华楠[1] 赵振华[1] 梁业如[1] 石建英[1] 吴丁财[1] 刘鸿[1] 符若文[1] 

机构地区：[1]中山大学化学与化学工程学院,广东广州510275

出　　处：《催化学报》2011年第2期321-324,共4页

基　　金：中国科学院大连化学物理研究所催化基础国家重点实验室开放课题(N-10-01);中央高校基本科研业务费专项资金(10lgpy35)

摘　　要：选用两种孔径不同的炭气凝胶CA125和CA500制备了碳含量为20%的TiO2/CA光催化剂,采用X射线衍射、扫描电镜和N2吸附-脱附对催化剂进行了表征,并考察了其光催化降解甲基橙反应性能.结果表明,TiO2/CA样品中TiO2主要以锐钛矿相存在,伴随有少量的金红石相,且均匀分散于炭气凝胶的表面.催化剂的孔隙率分析表明,孔结构直接影响到催化剂的光催化活性,以中孔为主的TiO2/CA125活性要远高于TiO2/CA500.这主要源于中孔良好的吸附性能及其合适的空间限域效应.Two kinds of carbon aerogel（CA） ,CA125 and CA500,with pore diameters of ～18 nm and 50 nm,respectively,were used as supports to prepare TiO2/CA photocatalysts with the CA content of 20%. X-ray diffraction,scanning electron microscopy and N2 adsorption-desorption were used to characterize the crystal structure,morphology,and pore structures of the TiO2/CA photocatalysts,respectively. The loaded TiO2 was mainly anatase with a little amount of rutile,which was homogeneously dispersed on the CA support. The activity of TiO2/CA125 was much higher than that of TiO2/CA500 in the photodegradation of methyl orange. The photodegradation rate over TiO2/CA is mainly influenced by the pore structure of the catalysts. The favorable adsorption and suitable confinement effect of mesopore structure are beneficial to the photodegradation of methyl orange. Therefore,TiO2/CA125 with the large amount of mesopores displays the higher photocatalytic activity than TiO2/CA500.

关 键 词：炭气凝胶 氧化钛 限域效应 光催化 甲基橙 降解 

分 类 号：X703[环境科学与工程—环境工程]