Ta掺杂提高TiO_2光催化效率及对微观结构的调制  

Enhanced photocatalytic activity and modulated micro-structure of TiO_2 by Ta doping

作　　者：付诚新 张宁[2] 吴义涛 刘佳琪[1] 宫银燕[1] 

机构地区：[1]中国计量大学材料科学与工程学院,浙江杭州310018 [2]济南大学材料科学与工程学院,山东济南250022

出　　处：《中国粉体技术》2017年第2期44-48,共5页China Powder Science and Technology

基　　金：国家自然科学基金;编号:51402277

摘　　要：采用Ta元素掺杂TiO_2光催化剂,研究掺杂引起的光催化效率变化、微观结构改变和催化剂改性的机制。采用溶胶凝胶法制备不同浓度的Ta元素掺杂纳米TiO_2光催化剂,并通过降解罗丹明B表征其光催化性能。通过X射线衍射、拉曼光谱和X射线光电子能谱分析Ta掺杂纳米TiO_2催化剂晶相、微观结构、元素组成和化合价等。结果表明:Ta掺入纳米TiO_2催化剂后,Ta原子将取代Ti的位置,以Ta^(5+)形式存在于TiO_2晶格中,促进掺杂样品中形成氧空位,可以有效提高电子密度,并抑制光生载流子复合,从而提高催化效率。当掺杂比例n_(Ta)/n_(Ti)为3%时,光催化效率最高,光照2 h对罗丹明B降解率高达83.8%,是未掺杂样品的2倍以上。The present work improved the photocatalytic activity of TiO2 nanoparticles by Ta doping, and investigated the modification of the crystal microstructure due to incorporation of Ta and the fimdamental mechanism for the enhanced photodegradation performance. Ta-doped TiO： photocatalysts with different Ta dopant concentrations were prepared by a sol-gel method. Photocatalytic activity were valued by the degradation of Rhodamine B. X-ray diffi＇action （XRD）, Raman spectroscopy and X-ray photoelectron spectroscopy （XPS） measurements were used to investigate the influence of Ta doping on the microstructure and electronic properties of TiO：. The results show that Ta5＋ is doped in TiO2 in a substitutional mode by replacing Tit＋, and the incorporation of Ta facilitate the formation of oxygen vacancies. The presence of Ta^5＋ and oxygen vacancies can increase the electron density and prevent the recombination of photogenerated carriers, and thus enhance the photocatalytic activity of TiO2. It is found that the Ta-3 photocatalyst exhibits the highest degradation efficiency of Rodamine B at 83.8% under nature light irradiation for 2h, which is more than twice that of undoped sample.

关 键 词：TIO2纳米颗粒 Ta掺杂 光催化 

分 类 号：TQ426[化学工程]