水热法合成纳米CdWO_4及其光催化性能研究  

Preparation of CdWO_4 particles via a hydrothermal method and its photocatalytic activities

作　　者：马延会[1] 田晓璇[2] Ma Yanhui;Tian Xiaoxuan(North China Electric Power InstituteCo.,Ltd,Beijing 100045,China;Xi’an Thermal Power Research Institute Co.,Ltd,Xi’an 710003,Shaanxi,China)

机构地区：[1]华北电力科学研究院有限责任公司,北京100045 [2]西安热工研究院有限公司,西安710003

出　　处：《工业催化》2019年第3期33-37,共5页Industrial Catalysis

基　　金：国家自然科学基金(51504104)

摘　　要：通过水热法合成光催化性能良好的纳米CdWO_4。采用粉末X射线衍射、扫描电子显微镜研究溶液pH值及水热温度对CdWO_4微观形貌、晶体结构的影响。在紫外线光照下甲基橙降解实验中测试制备的CdWO_4纳米颗粒的光催化活性。结果表明,合成的催化剂为单斜晶系CdWO_4晶体,不含其他杂质。水热反应温度150℃时,随着溶液pH值的降低(10.0→9.20→8.60),CdWO_4颗粒逐渐减小,紫外光照射90 min后,甲基橙降解率分别为20%、 26%和40%,其降解动力学参数k分别为0.002 3 min^(-1)、0.003 3 min^(-1)、0.005 7 min^(-1)。水热反应温度升高至180℃,pH为8.60时,合成的CdWO_4催化剂呈细针状,具有最高的光催化活性,光照90 min后,甲基橙降解率70%,降解动力学参数k=0.026 2 min^(-1)。CdWO 4 photocatalyst was synthesized via a hydrothermal method and characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD) to determine effects of pH value and hydrothermal temperature on CdWO 4 micromorphology and crystal structure.The photocatalytic activity of CdWO 4 photocatalyst was evaluated by degrading of methyl orange under UV-light irradiation.Results show that the synthesized photocatalyst is a pure monoclinic phase of CdWO 4 without any impurities.When hydrothermal reaction temperature is 150 ℃,with the decrease of pH value (10.0→9.20→8.60),particle size of CdWO 4 decrease.The degradation rate of methyl orange under ultraviolet light for 90 min was 20%,26% and 40%,respectively.The corresponding kinetic rate constant of the degradation k is 0.002 3 min^-1 ,0.003 3 min^-1 ,and 0.005 7 min^-1 , respectively.When hydrothermal reaction temperature is 180 ℃ and pH value is 8.60,the CdWO 4 photocatalyst is fine needles-likes and possess the highest catalytic activity, of which the degradation rate of methyl orange under is up to 70% and corresponding k is 0.026 2 min^-1 .

关 键 词：催化化学 光催化降解 CDWO4 纳米粉体 甲基橙 水热法 

分 类 号：O643.36[理学—物理化学] TQ034[理学—化学]