微波超声强化银掺杂TiO_2催化剂光催化活性的研究  

Study on the microwave and ultrasonic enhanced photo-catalytic activity of Ag doped TiO_2 photo-catalyst

作　　者：卢月洁 王鑫[1] 毕先均 

机构地区：[1]云南师范大学化学化工学院,云南昆明650500

出　　处：《化学研究》2016年第6期748-755,共8页Chemical Research

基　　金：国家自然科学基金资助项目(20663007)

摘　　要：在[Bmim]PF6离子液体介质中,用溶胶凝胶-微波干燥法制备银掺杂TiO_2光催化剂TiO_2-Ag.以甲基橙为有机污染物,用微波超声组合仪分别在微波(MW)、紫外(UV)、紫外-微波(UV-MW)和超声-紫外-微波(UT-UV-MW)4种条件下降解甲基橙溶液,考察银掺杂对催化剂降解甲基橙的影响,以提高催化剂光催化性能.分别用X射线衍射分析(XRD)、扫描电子显微镜(SEM)、能谱分析(EDS)、热重-差示扫描量热分析(TG-DSCDTG)、固体紫外可见分析(Uv-vis)和红外分析(IR)对TiO_2-Ag催化剂进行测试表征.结果表明,优化条件下制备TiO_2-Ag催化剂在UV、UV-MW和UT-UV-MW条件下降解甲基橙35 min后,甲基橙的降解率分别为88.05%、93.98%和99.84%;降解甲基橙55min后,甲基橙的降解率分别为98.79%、99.05%和99.90%.在UTUV-MW条件下降解25min后,降解率接近100%.表明TiO2-Ag催化剂具有较高的光催化降解活性,微波超声协同作用加快光催化降解反应进行.催化剂的结构分析表明,银掺杂抑制了二氧化钛晶相的转变,使相变温度升高,稳定性增强;同时,催化剂向可见光区扩宽了光响应范围,提高了量子效率,从而光催化性能得以提高.Ag doped TiO_2photo-catalyst TiO_2-Ag was prepared by the sol-gel and microwave drying method in ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate.In order to improve TiO_2-Ag photo-catalytic degradation performance,the activity of TiO2-Ag for the degradation of methyl orange as organic pollutants was investigated respectively under the four conditions of microwave（MW）and ultraviolet（UV）,microwave-ultraviolet（UV-MW）,ultrasonic-ultraviolet-microwave（UT-UV-MW）in the microwave ultrasonic instrument.The Xray diffraction analysis（XRD）,scanning electron microscopy（SEM）,energy spectrum analysis（EDS）,thermogravimetry-differential scanning calorimetry（TG-DSC-DTG）,solid ultraviolet-visible analysis（UV-Vis）and infrared analysis（IR）were used to characterize the structure of the Ag doped TiO_2 catalyst.The results indicated that the degradation rate of methyl orange was respectively 88.05%,93.98% and 99.84% under three conditions of UV,UV-MW and UT-UV-MW for the degradation time 35 min.However,the degradation rate of methyl orange could respectively reach 98.79%,99.05% and 99.90% under three conditions of UV,UV-MW and UT-UV-MW for the degradation time 55 min.In the UT-UV-MW Degradation 25 min later,the degradation rate was nearly 100%.The structure analysis of the catalyst showed that Ag doped TiO_2 could suppress the variety of titanium dioxide crystal phase transition,resulting in the crystal phase transition temperature increased.Meanwhile,Ag doped TiO_2 could also broaden the visible region to the light response range and increase quantum efficiency,causing the photo-catalytic performance improved.

关 键 词：离子液体 银掺杂 TIO2光催化剂 微波超声强化 光催化活性 

分 类 号：O643.32[理学—物理化学]