摘要
本文通过微波辅助溶胶-凝胶法制备Dy^(3+)掺杂TiO_2微纳米晶。通过X射线衍射仪(XRD)、傅里叶红外光谱仪(FTIR)和紫外可见光谱(UV-vis)对样品的物相成分、分子键价结构和光催化性能进行表征和分析。结果表明:Dy^(3+)掺杂量对TiO_2微纳米晶的相变有一定的影响,且在锐钛矿到金红石的晶型转变过程有抑制的作用,当Dy^(3+)掺杂量为1.2wt.%时,晶粒大小为11.5nm,样品几乎保持单一锐钛矿物相。表面存在羟基,它可以捕捉空穴,形成羟基自由基,有利于光催化降解有机物。Xe灯下光照50min后,典型样品对MB的光催化反应速率为k=0.07461 min^(-1)和降解率为97.14%,这可能与一定量Dy^(3+)的引入有关。Dy^(3+)可以捕捉电子,生成g O_2-。而空穴则能和样品表面的羟基反应生成g OH,能有效抑制光生电子和空穴对的复合,从而使典型样品具有较高的光催化活性。
Dy3+doped TiO2 nanocrystals were prepared by microwave assisted sol-gel method. The phase composition,molecular bond structure and photocatalytic properties of the samples were characterized and analyzed by X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FT-IR),Ultraviolet visible spectroscopy(UV-Vis). The results revealed that the doping amount of Dy3+had a certain effect on the phase transition of TiO2 micro-nanocrystals,and had an inhibitory effect on the crystal transition process from anatase to rutile. When the doping amount of Dy3+was 1.2 wt.%,the typical sample almost remained a single anatase mineral phase. When the doping amount of Dy3+was1.2 wt.%,the crystallite size was 11.5 nm. Hydroxyl groups existed on the surface of the typical sample,which can capture the holes and form hydroxyl radicals,conducive to photocatalytic degradation of organic compounds. After 50 min in Xe light irradiation,the photocatalytic reaction rate of the typical sample to MB was k = 0.07461 min-1 and the degradation rate was 97.14%,which may be related to the introduction of a certain amount of Dy3+,which can capture electrons and generate g O2-. The hole can react with the hydroxyl group on the surface of the sample,formin g OH,which can effectively inhibit the combination of photogenerated electron-hole pairs. Thus,the typical sample had a higher photocatalytic activity.
作者
王书媚
田修营
谢刘平
Wang Shumei;Tian Xiuying;Xie Liuping(Hunan Provincial Key Laboratory of Fine Ceramics and Powder Materials,School of Materials and Environmental Engineering,Hunan University of Humanities,Science and Technology,Loudi,417000,China)
出处
《山东陶瓷》
CAS
2019年第1期3-7,共5页
Shandong Ceramics
基金
湖南人文科技学院校级科学研究项目(2016QN11)
湖南省教育厅优秀青年项目(17B138)
湖南省自然科学基金青年项目(2018JJ3251)
精细陶瓷与粉体材料湖南省重点实验室开放课题(TC201701)
