氧缺陷型TiO_(2-x)可见光催化性能的研究  

Study of the Photocatalytic Performance of Oxygen-deficient TiO_2 Active in Visible Light

作　　者：操小鑫[1] 陈亦琳[1] 林碧洲[1] 高碧芬[1] 

机构地区：[1]华侨大学材料科学与工程学院,厦门361021

出　　处：《无机材料学报》2012年第12期1301-1305,共5页Journal of Inorganic Materials

基　　金：国家自然科学基金(21003055;21103054);福建省自然科学基金(2012J01043);华侨大学高层次人才资助项目(06BS213)~~

摘　　要：采用氢气还原法制备氧缺陷型二氧化钛(TiO2-x),考察氧气氛中不同返烧温度对TiO2-x性能的影响.利用X射线光电子能谱、电子自旋共振谱、紫外?可见漫反射光谱和荧光光谱等技术对样品的表面化学状态、氧缺陷位的种类、光吸收性能和光生载流子的分离效率等性质进行了表征,并以气相的苯为模型污染物,研究催化剂样品在可见光(λ>400nm)照射下的光催化氧化能力.结果表明,与未返烧的催化剂相比,返烧后TiO2-x对苯的光催化氧化降解能力显著提高,反应4h、催化剂活性稳定后,经300℃返烧的TiO2-x样品对苯的转化率为36.9%,是未返烧样品的5.3倍.还原过程中生成的体相氧缺陷位(束缚单电子的氧空位)是催化剂具有可见光催化性能的主要原因,返烧热处理减少了催化剂表面氧缺陷位(Ti3+)的浓度并有效地抑制了光生载流子的复合.Oxygen-deficient titanium dioxide （TiO2.x） was prepared by heating TiO2 in H2 atmosphere, followed by the post-calcination in at different temperatures. The physicochemical properties of the products were characterized by X-ray photoelectron spectroscope （XPS）, electron spin resonance （ESR）, UV-Vis diffuse reflectance spectrum （UV-Vis DRS） and photoluminescence spectrum （PL）. The photocatalytic activity of the as-prepared samples was determined by the degradation of gas-phase benzene under visible light （λ〉 400 nm） irradiation. The results show that the TiO2_x post-heated at 300 ℃ exhibits the highest photocatalytic activity. After photocatalytic oxidation for 4 h, the conversion rate of benzene over the catalyst is up to 36.9% at steady state, which is 5.3 times as much as that on the untreated sample. The enhanced photocatalytic performance of the TiO2.x is related to the amount of the oxygen vacancies in matrix （single-electron-trapped oxygen vacancies）. The postcalcination successfully reduces the surface oxygen vacancies （Ti3＋）, efficiently hindering the photoinduced carriers from recombination.

关 键 词：氧缺陷位 TIO2 可见光 光催化 

分 类 号：O643[理学—物理化学]