摘要
以钛酸四丁酯和硝酸镧为原料,采用溶胶-凝胶法,制备出La掺杂TiO2膜.采用X射线光电子能谱(XPS)、傅立叶红外(FTIR)、X射线衍射(XRD)、低温氮物理吸附、扫描电子显微镜(SEM)、紫外-可见漫反射光谱(DRS)对光催化剂的晶相结构、光谱特征和表面结构进行表征.以气相甲苯为模型物,在自制光催化反应器中考察了催化剂在可见光下对气相有机污染物的去除性能.结果表明,La掺杂可诱发催化剂的可见光催化活性,500℃热处理的2.8%molLa掺杂TiO2膜在60min内即可完全去除6110.18mg/m3的气相甲苯;掺入的La主要以La2O3的形式存在,同时有一部分形成Ti-O-La键;La掺杂可抑制TiO2锐钛矿相向金红石相转变、提高相转变温度、减小晶粒尺寸及增大催化剂比表面积;La/TiO2薄膜表面光滑、致密,La的引入能有效抑制TiO2膜气孔的产生;La掺杂可提高TiO2在可见光区的吸收,使催化剂吸收边向长波移动;La的f轨道的电子跃迁和TiO2晶格扭曲是催化剂可见光活性提高的重要原因.
Visible light response lanthanum-doped TiO2 film was prepared by Sol-Gel method using Ti(OBu)4 and La(NO)3.6H2O as raw materials.XPS,FTIR,XRD,N2(77K)adsorption,SEM and DRS were used for catalyst char-acterization.Gaseous toluene removal was used for photocatalytic activity test.The results show that La dopant can induce visible light activity.The sample of 2.8-La/TiO2-500 exhibites the highest activity,which can remove toluene of initial concentration 6110.18mg/m3 completely within 60min.La3+ disperses onto TiO2 as the form of La2O3 and partly as the form of Ti-O-La bond.La dopant can inhibit phase transformation,enhance phase transformation temperature and is also beneficial to gain smaller particle size and large surface area of TiO2.Compared with pure TiO2 film,La dopant can also inhibit the generation of air-pores and the surface of La/TiO2 film is more dense and smooth.Electrons transfer of f level of La and the destortion of TiO2 lattice is the main reason for the enhancement of visible-light activity.
出处
《无机材料学报》
SCIE
EI
CAS
CSCD
北大核心
2010年第9期928-934,共7页
Journal of Inorganic Materials
基金
黑龙江省杰出青年基金(JC200801)
国家自然科学基金(30771692)
黑龙江省科技攻关项目(GB06B501-3)~~