钙钛矿La_(1-x)Sr_xMnO_3纳米晶光催化活性  

Photocatalytic activity of perovskite La_(1-x)Sr_xMnO_3 nanocrystal

作　　者：董抒华[1] 田贵山[1] 冯柳[2] 

机构地区：[1]山东理工大学材料科学与工程学院,淄博255049 [2]山东理工大学测试中心,淄博255049

出　　处：《中国有色金属学报》2008年第7期1353-1357,共5页The Chinese Journal of Nonferrous Metals

基　　金：国家高技术研究发展计划资助项目(2001AA333040)

摘　　要：采用柠檬酸络合法制备La1-xSrxMnO3(x=0,0.05,0.1,0.3,0.5)纳米光催化剂,应用XRD、UV-vis和SEM等技术表征这些纳米晶的物化性质及微观结构,并研究其对亚甲基蓝紫外光照射降解的光催化活性。结果表明:所得光催化剂为钙钛矿型,均为立方相,原子Sr替代钙钛矿A位La进入晶格中引起晶胞收缩,晶格产生畸变。掺杂Sr后LaMnO3的吸收带边发生明显的红移。Sr最佳掺杂量x=0.1,所形成的La0.9Sr0.1MnO3光催化剂分散性好、尺寸分布较窄,经150 min光照射后光降解率可达67.1%,比LaMnO3作为光催化剂提高32.2%。掺杂Sr后引起的点缺陷-氧空位浓度增加是掺杂Sr后的LaMnO3具有高效光催化活性的主要原因。Nanophotocatalysts La1-xSrxMnO3 （x=0, 0.05, 0.1, 0.3, 0.5） were prepared by citric acid complexometry. In order to obtain physicochemical properties and microstructure, these powders were characterized by XRD, UV-vis and SEM. The photocatalytic activities of these powders in the methylene blue were studied. The results show that these catalysts are cubic and Sr substitutes for La to diminish the crystal cell. The distortion of lattice is caused. The photoabsorption edges have obvious red shift after doping Sr^2＋. Sr^2＋ optimal doping amount is 0.1, and La0.9Sr0.1MnO3 photocatalysis is well dispersed and the size is narrow. The photodegradation rate irradiated for 150 min reaches 67.1% when La0.9Sr0.1MnO3 serves as the photocatalyst, which exceeds 32.2% when LaMnO3 uses as the catalyst. The improvement of photocatalytic activity could be mainly attributed to the increase of the point defect, i.e, the oxygen vacancy concentration results from the Sr^2＋ doping.

关 键 词：钙钛矿 柠檬酸络合 Sr掺杂 光催化 

分 类 号：O614.33[理学—无机化学]