摘要：为了获得La-Co-Mn超细粒子,探究Mn掺杂量对超细粒子结构、形貌及光催化活性的影响,采用溶胶-凝胶法结合真空干燥技术制备目标粒子,利用热重-差热分析、X射线衍射、透射电子显微镜等测试方法进行表征,将产物作用于紫外光下的甲基橙溶液以探讨其催化活性。结果表明:850℃热处理可获取粒径介于30~50 nm的类球型颗粒,晶相组成为LaMn_xCo_1-xO₃和La₂O₃;Mn³⁺与Co³⁺共同占据晶格B位结点构成导带;氧空位数量与Mn掺杂量相关,当Mn掺杂摩尔分数x为0.3时,LaMn_xCo_1-xO₃晶格的氧空位数量较多,光催化活性较高。

关键词：超细粒子；制备；结构；光催化；稀土

Abstract： To obtain La-Co-Mn ultrafine particles and research influence of Mn-doping dosage on the structure, morphology and photocatalytic ability of them, the target particles were synthesized using so1-gel method combining with the vacuum drying technology. The products were characterized by TG -DSC, XRD and TEM. The catalysis activities were evaluated in the degradation reaction of methyl orange under UV lights. The results show that the spherical particles with size between 30 and 50 nm can be gained by thermal treating at 850 ℃, which are mainly composed of LaMn_xCo_1-xO₃ and La₂O₃. Mn³⁺ together with Co³⁺ occupies B sites in the lattice. Oxygen number is related to the Mn-doping dosage. When the Mn-doping molar fraction x equals 0.3, the number of oxygen vacancies is rather large in crystal lattice of LaMn_xCo_1-xO₃, and the photocatalytic activity is rather high. 

Keywords: ultrafine particle; preparation; structure; photocatalytic; rare earth