焙烧温度对1.0wt%Sm-TiO2纳米粉体可见光催化活性的影响  

Effect of Calcined Temperature on Visible Photocatalystic Activity of Nano-TiO_2 Powders Doped 1.0wt% Sm

作　　者：彭富昌[1] 李亮[1] 崔晏[1] 高洪林 柳清菊[2] 

机构地区：[1]攀枝花学院材料工程学院.四川攀枝花617000 [2]云南大学材料科学与工程学院,云南昆明650091

出　　处：《材料科学与工程学报》2018年第1期35-40,共6页Journal of Materials Science and Engineering

基　　金：国家自然科学基金资助项目(51262030); 四川省教育厅自然科学基金资助项目(17ZB0227); 云南省微纳材料与技术重点实验室开放基金资助项目(KF2015005)

摘　　要：采用溶胶-凝胶法制备了经不同温度焙烧的1.0wt%Sm掺杂TiO_2纳米粉体(SmTiO_2)。通过对样品进行表征,以亚甲基蓝(MB)作为目标降解物,考察了不同焙烧温度条件下制备的Sm-TiO_2样品对MB的光催化降解效果。结果表明,焙烧温度对Sm的实际掺杂效果影响不大,Sm掺入TiO_2后在表面存在Sm^(3+)和Sm^(2+)两种价态;Sm掺杂抑制了TiO_2从锐钛矿相向金红石相转变,抑制了光生e^-/h^+的复合;焙烧温度升高,样品中金红石相含量增加,晶粒尺寸增大。焙烧温度500℃时样品的吸收光谱阈值红移最大,光生e^-/h^+的复合率低,1.0wt%Sm-TiO_2样品在普通日光灯下对MB在6h内的降解率达96.86%,明显高于同类产品P25的降解率(56.52%)。Nano-TiO_2 powders with 1.0 wt%Sm doping at different calcined temperature were prepared by a sol-gel method.The photocatalytic activity of Sm-TiO_2 samples was investigated at different calcined temperatures by measuring the degradation rate of methylene blue（MB）under the irradiation of fluorescent lamp.The results show that calcined temperature has little effect on doping of Sm.Samarium exist as Sm^（3＋） and Sm^（2＋） two kinds of valence state on the surface of TiO_2.Sm doping inhibited the phase transition from anatase to rutile and decreased the recombination of photogenerated electron-hole pairs.With the increment of calcination temperature,the grain size and rutile phase content of the samples increases.The samples calcined at 500℃ showed largest red shift of the absorption edge for the visible-light.The photocatalytic activity of the 1.0 wt% Sm-TiO_2 samples calcined at 500℃ is 96.86% within 6 h under the irradiation of fluorescent light,which is significantly higher than 56.52% of P25 produced by Degussa under the same experimental conditions.

关 键 词：Sm掺杂 纳米TIO2 焙烧温度 光催化 

分 类 号：O643[理学—物理化学] O644[理学—化学]