水热法制备Cu掺杂可见光催化剂BiVO_4及其光催化性能研究  

Preparation and Photocatalytic Activity of Cu-doped BiVO_4 Photocatalysts Fabricated by Hydrothermal Method

作　　者：陈渊[1,2] 周科朝[1] 黄苏萍[1] 李志友[1] 刘国聪[2,3] 

机构地区：[1]中南大学粉末冶金国家重点实验室,长沙410083 [2]玉林师范学院新材料研发和化学生物传感技术所,玉林537000 [3]中南大学化学化工学院,长沙410083

出　　处：《无机材料学报》2012年第1期19-25,共7页Journal of Inorganic Materials

基　　金：广西科学技术研究和开发项目(2010GXNSFB013018);广西高校优秀人才资助项目(2009G033);广西教育厅科研项目(200911LX368);玉林师范学院重点科研项目(2010YJZD13;2011YJD14)~~

摘　　要：以Bi(NO3)3.5H2O、NH4VO3、Cu(NO3)2.3H2O为原料,采用水热法合成了Cu-BiVO4光催化剂,并利用X射线衍射(XRD)、扫描电镜(SEM)、X射线光电子能谱(XPS)、紫外漫反射(UV-Vis)等测试手段对催化剂进行了表征.结果表明,提高前驱液pH值,可得到单斜晶系白钨矿型Cu-BiVO4光催化剂,BiVO4的晶型结构并未随着Cu掺入量的增加而改变.光催化剂中的Cu元素以CuO和Cu2O的形式存在.Cu的引入使可见光吸收带发生红移,吸收强度明显提高.可见光催化降解亚甲基蓝溶液的结果表明,Cu掺杂有利于提高BiVO4的活性.其中pH值为5.0、Cu掺入量为1.0wt%的BiVO4具有最好的光催化效果,可见光照射60 min后,对初始浓度为10 mg/L的亚甲基蓝溶液的最高降解率由纯BiVO4的57.4%提高到97.8%.并对Cu掺入后光催化活性提高的机理进行了分析.Cu-BiVO4 photocatalysts were prepared by hydrothermal method using Bi（NO3）3.5H2O,NH4VO3 and Cu（NO3）2.3H2O as raw materials.The samples were characterized by X-ray diffraction（XRD）,scanning electron microscope（SEM）,X-ray photoelectron spectroscope（XPS） and UV-Vis diffusion reflectance spectra（UV-Vis）.The results show that highly crystalline monoclinic scheelite structure of Cu-BiVO4 is obtained by increasing the pH value,and the crystal structures of BiVO4 are no change with the increasing of Cu dopant.XPS results reveal that the doped Cu species exists in the form of CuO and Cu2O.The Cu-BiVO4 catalyst has a significant red-shift in the absorption band in the visible region,and the absorption intensity increases greatly for the composite catalyst compared with pure BiVO4.The Cu-BiVO4 photocatalysts enhance the photocatalytic activities for degradation of methylene blue（MB） under visible light irradiation.When pH value is 5.0 and Cu dopant is 1.0wt%,the photocatalytic activities reach the maximum.After visible light irradiation for 60 min,the removal rate of MB by Cu-BiVO4（1.0wt% Cu） at 10 mg/L initial concentration increases to 97.8% while the removal rate of MB by pure BiVO4 is only 54.7%.The mechanism of enhanced photocatalytic activity is also discussed.

关 键 词：水热法 Cu-BiVO4 光催化 亚甲基蓝 制备 

分 类 号：O643[理学—物理化学]