Fe^(3+)、Eu^(3+)共掺纳米TiO_2光催化降解N-(2-苯并咪唑基)-氨基甲酸甲酯  

Preparation of TiO_2 nanoparticles co-doped with Fe^(3+) and Eu^(3+) and photocatalytic degradation of carbendazim

作　　者：谭春雷[1] 樊君[1] 姚飞[1] 孙洋[1] 胡晓云[2] 魏嵩[1] 闫森[1] 梁旭华[1] 

机构地区：[1]西北大学化工学院,陕西西安710069 [2]西北大学物理系,陕西西安710069

出　　处：《化学工程》2012年第2期17-22,共6页Chemical Engineering(China)

基　　金：国家自然科学基金资助项目(20876125)

摘　　要：采用溶胶-凝胶-微波法制备Fe3+、Eu3+共掺杂纳米TiO2(Fe/Eu-TiO2),并通过紫外-可见吸收光谱(UV-Vis)、荧光光谱(FS)、X射线衍射(XRD)、扫描电镜(SEM)、比表面积测定(BET)等手段对其进行表征。结果表明:在500℃氮气保护下退火制得的Fe/Eu-TiO2为锐钛矿相纳米颗粒,平均粒径为20—50 nm;对可见光的响应范围为370—770 nm。光催化降解N-(2-苯并咪唑基)-氨基甲酸甲酯(多菌灵)的实验表明,Fe3+、Eu3+共掺杂对TiO2光催化表现出协同增效作用,在可见光下能产生更多的羟基自由基,对多菌灵降解速率常数kapp为0.046 66 min-1,大于分别单掺Fe3+和Eu3+的TiO2纳米粒子。Nanoparticles of TiO2 co-doped with Fe3＋ and Eu3＋ were prepared in anhydrous ethanol media by sol-gel-microwave method.Fe/Eu-TiO2 photocatalysts were prepared by modification of TiO2 fine particles of anatase structure through heating in N2 at 500 ℃.The as-prepared photocatalysts were characterized by UV-Vis,FS,XRD,SEM and BET.The photodegradation of carbendazim was used as probe reaction to examine their photoactivity and analyze the apparent kinetic constants.The results show that Fe3＋ and Eu3＋ co-doped TiO2 whose crystalline size is in the range of 20-50 nm extends the absorption spectra into the visible region over the range 370-770 nm,thus presenting the best photocatalytic activity under UV and visible light.Meanwhile,the photocatalytic degradation rate constant kapp（0.046 66 min-1） of Fe/Eu-TiO2 is higher than that of Fe3＋ or Eu3＋ single-doped TiO2.The kinetics and mechanism of the reaction indicates that the Eu3＋ and Fe3＋ co-doping promotes the photocatalysis by capturing the photogenerated electrons and may induce the formation of HO·.

关 键 词：溶胶-凝胶-微波法 二氧化钛 Fe3+、Eu3+共掺杂 光催化降解 N-(2-苯并咪唑基)-氨基甲酸甲酯 

分 类 号：O643.3[理学—物理化学]