异质结型CdS/TiO_2介孔催化剂光催化降解VOC研究  

On the VOC photocatalytic degradation of the heterojunction type CdS/TiO_2 mesoporous catalyst

作　　者：龚维[1] 汤建庭[1] 张鹏[1] 杨统军[1] 蔡铁军[1] 邓谦[1] 

机构地区：[1]湖南科技大学化学化工学院,湖南湘潭411201

出　　处：《安全与环境学报》2012年第6期62-66,共5页Journal of Safety and Environment

基　　金：湖南省科技计划项目(2011FJ4154);催化基础国家重点实验室开放课题基金项目(N-11-13)

摘　　要：用水热法制备了CdS/TiO2异质结型介孔光催化剂,并用氮气吸脱附、扫描电镜、透射电镜、红外光谱、荧光光谱、差热-热重等手段对其进行了表征。结果表明,CdS掺杂TiO2具有典型的介孔结构和较高的比表面积。其比表面积为101.9m2/g,孔体积为0.376 cm3/g,孔径的最可几分布为2.7 nm,颗粒粒径在10nm左右。以丙酮和甲醇模拟VOC底物,评价了催化剂的紫外光催化活性。设计正交试验,考察了催化剂制备过程中十六烷基三甲基溴化铵(CTAB)用量、硫化镉掺杂量、活化温度、水热温度、水热时间等因素对其光催化性能的影响。试验结果表明,各因素对光催化活性的影响大小顺序为:CTAB用量、硫化镉掺杂量、焙烧温度、水热温度、水热时间。最佳的催化剂制备方案为:CTAB用量0.6 g,硫化镉掺杂量0.1%,水热温度180℃,水热时间3 h,活化温度350℃。在反应气体积流速为10mL/min条件下,0.1g的最佳催化剂可将初始质量浓度为15.62 g/m3的丙酮、3.11 g/m3的甲醇完全消除。The paper intends to report our study results of the VOC photocatalytic degradation of the heterojunction type CdS/TiO2 meso- porous catalyst with the hydrothermal method. For our research pur- pose, we have defined and analyzed the concepts of nitrogen adsorp- tion-desorption, electronic transmission microscopy （TEM）, IR spec- troscopy, FL spectroscopy and thermo-gravimetric-differential thermal analyzer （TG - DTA）. The results of our experiments indicate that the CdS doped TiO2 catalyst can be taken as characteristic of the typi- cal mesoporous structure and higher specific surface area. The parti- cles of the catalyst enjoy their specific surface area of 101.947 m2/g, the pore volume of 0.376 cma/g, with the most probable distribution of aperture of 2.7 nm, with the size around 10 nm. At the same time, we have found that their photocatalytic activity can be evaluated by eliminating the acetone and methanol as the simular of VOC under UV-light irradiation. Next, we have laid out a set of orthogonal ex- periments in hoping to find the optimal preparation conditions with the orthogonal factors, including the amount of hexadecyl tfimethyl am- monium bromide （CTAB）, the doping content of CdS, the tempera- ture of calcination, the temperature of hydrothermal reaction, as well as the time of hydrothermal reaction. The orthogonal experiments we have done prove that the above factors influencing photocatalytie ac- tivities tend to follow an order like the amount of hexadecyl trimethyl ammonium bromide 〉 doping content of CdS 〉 the temperature of cal- cination 〉 the temperature of hydrothermal reaction 〉 the time of hy- drothermal reaction. And, finally, we have prepared a catalyst of the highest photocatalytic activity in the following procedure ： taking O. 6 g of hexadecyl trimethyl ammonium bromide and doping 0.1% CdS as a content, while proceeding with the experiments for calcinations done at the temperature of 180 ~C, and that of hydrothermal reaction at the temperature of 350 ~C, in a period

关 键 词：物理化学 光催化 TiO2 CDS 异质结 挥发性有机物 

分 类 号：O643.3[理学—物理化学]