摘要
为了进一步提高商品P25光催化活性,采用了一种温和且简单的水热方法对其进行后处理,整个处理过程只需加入去离子水。通过对处理前后的样品进行X射线衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)以及氮气吸脱附等温线等测试表明:处理后的样品粒径减小,介孔结构更加突出,比表面积、平均孔径和孔容等相对于商品P25都有大幅提高,对入射光吸收有明显红移。同时,还考察了不同后处理条件对TiO2形貌和光催化活性的影响,包括温度、时间和溶剂类型等。结果表明:当水热温度为180℃、处理时间为4 h时,TiO2对染料的光催化降解效果最好,反应速率常数(kapp=0.11 min^-1)是未处理商品P25的3倍(kapp=0.034 min^-1),且反应溶液的总有机碳(TOC)去除率达64.63%,证明有机物得到了较为彻底的分解。自由基淬灭实验显示:经水热后处理的样品可以在光照下产生更多的活性氧化物种,因而加快了有机染料的降解过程。
In this research,a facile and simple hydrothermal method was employed in the post-treatment of P25,only with the addition of deionized water during the whole treating process.From the characterizations of XRD patterns,SEM images,TEM images and N2 adsorption-desorption isotherms,the average particle size of the post-treated sample decreased,the mesoporous structure was prominent in the post-treated samples,the BET surface area,average pore diameter and total pore volume were all increased a lot compared to the untreated P25,and the absorption spectrum had an obvious red shift to the incident irradiation.In addition,the effects of some controlled conditions such as treating temperature,time and type of solvents on the morphology and photocatalytic property of TiO2 were also discussed.As a result,the TiO2 that hydrothermal post-treated at 180℃for 4 h showed the best photocatalytic activity with the kapp value of 0.11 min-1,which was three times of the untreated P25(0.034 min^-1).Furthermore,the TOC removal of the reactant solution reached 64.63%,which proved that the organic dye had a relatively complete decomposition.From the radical quenching research,more active oxidative species especially the photoinduced holes could be produced from the post-treated sample under the irradiation,which were helpful for the degradation of the organic dye.
作者
李凯静
吴松浩
韩冰
董立峰
孙琼
LI Kaijing;WU Songhao;HAN Bing;DONG Lifeng;SUN Qiong(College of Materials Science and Engineering,Qingdao University of Science and Technology,Qingdao 266042,China)
出处
《青岛科技大学学报（自然科学版）》
CAS
2020年第5期59-67,73,共10页
Journal of Qingdao University of Science and Technology:Natural Science Edition
基金
福州大学能源与环境光催化国家重点实验室开放课题项目(SKLPEE-KF201707).
关键词
TIO2
水热法
后处理
光催化
titanium dioxide
hydrothermal method
post-treatment
photocatalysis
