Ag/TiO_2复合纳米催化剂的制备和表征及其光催化活性  

Preparation and Characterization of Ag/TiO_2 Nanoparticle Catalyst and Its Photocatalytic Activity

作　　者：章福祥[1] 张秀[1] 陈继新[1] 刘智广[1] 高文亮[1] 金瑞彩[1] 关乃佳[1] 

机构地区：[1]南开大学-天津大学联合研究院

出　　处：《催化学报》2003年第11期877-880,共4页

基　　金：国家自然科学基金重点基金资助项目( 2 0 2 3 3 0 3 0 );教育部南开大学;天津大学科技合作项目;石油大学中国天然气集团催化重点实验室开放基金资助项目

摘　　要：采用光还原沉积贵金属法 ,制备了Ag/TiO2 复合纳米催化剂 .通过调节溶液的pH值控制TiO2 表面负载银的形貌 ,利用AAS ,XRD ,TEM和XPS等手段对样品进行了表征 .以苯胺氧化为模型反应 ,考察了Ag/TiO2 复合纳米催化剂样品的光催化活性以及银沉积量和沉积形貌对催化剂活性的影响 .结果表明 ,通过调控光还原沉积条件 ,可在平均粒径为 2 4nm左右的TiO2 颗粒上获得 3nm左右均匀分散的银粒子 ;在TiO2 上沉积适量的具有较高分散度的金属Ag ,能有效提高TiO2Ag/TiO 2 composite nanoparticle catalyst was prepared by photoreductoin-depos ition method. The morphology of silver particles could be changed by controlling pH val ue of the solution, and the well-dispersed silver particles (about 3 nm) were s uccessfully obtained on the surface of TiO 2 nanoparticles(ca 24 nm). The c a talyst samples were characterized by AAS, XRD, TEM and XPS techniques. The photo c atalytic activity of Ag/TiO 2 was measured by using photocatalytic oxidation of aniline as a model reaction, and the effects of Ag loading on the photocatalyti c activity were investigated. The photocatalytic oxidation of aniline indicated that the photocatalytic activity of TiO 2 nanoparticles could be greatly improv ed by depositing appropriate amount of silver on their surface. The morphology o f coated silver had a direct effect on the photocatalytic activity of Ag/TiO 2 catalyst. Well-dispersed silver particles with a proper loading could improve t he photocatalytic oxidation of aniline efficiently.

关 键 词：银 二氧化钛 复合纳米催化剂 形貌 光还原法 苯胺 光催化氧化 

分 类 号：O643.3[理学—物理化学]