合成温度对La_(0.85)K_(0.15)MnO_3纳米颗粒磁性能的影响  

Effect of Synthesis Temperature on Magnetocaloric Properties of La_(0.85)K_(0.15)MnO_3 Nanoparticles

作　　者：李丽荣[1] 赵娟[2] 王贵[2] 罗龙[3] 

机构地区：[1]内蒙古科技大学数理与生物工程学院,内蒙古包头014010 [2]广东海洋大学工程学院,广东湛江524088 [3]内蒙古科技大学材料与冶金学院,内蒙古包头014010

出　　处：《稀土》2012年第2期10-13,共4页Chinese Rare Earths

基　　金：国家自然科学基金项目资助(50672015)

摘　　要：采用非晶态配合物前躯体法在比较低的烧结温度合成了钙钛矿结构氧化物La0.85K0.15MnO3纳米颗粒,系统的研究了烧结温度对La0.85K0.15MnO3纳米颗粒磁性能的影响,用PPMS测量样品的居里温度和磁性能,结果表明烧结温度范围在600℃～1000℃之间,居里温度TC为274.5 K,和烧结温度没有明显关系,在H=2T时,烧结温度分别为600℃,800℃,1000℃,对应的磁熵变△SM分别是2.02 J/(kg.K),3.06 J/(kg.K),3.56 J/(kg.K),当烧结温度升高到1200°C时,居里温度TC为242.9K,通过控制烧结温度来调节La0.85K0.15MnO3纳米颗粒的磁性能。In this paper,the nanosized particles of La0.85K0.15MnO3 perovskite-type oxides were sucessfully synthesized at relatively low calcinated temperature by using amorphous heteronuclear complexing method.The relationship between magnetocaloric properties and the calcined temperature of La0.85K0.15MnO3 nanoparticles was investigated systematically.The result of PPMS（Physical Property Measurement System） measurement shows that the Curie temperature TC is 274.5 K and is independent of the calcined temperature within range of 600℃-1000℃,the maximum magnetic entropy changes close to TC（274 K） of the samples calcined at 600℃,800℃ and 1000℃ are 2.02,3.06 and 3.56 J/kg·K at H=2T.However,the Curie temperature of sample calcined at 1200°C for 10h is 242.9K,which means that the magneticaloric property of the La0.85K0.15MnO3 nanoparticles can be precisely controlled by adjusting the heat treatment process.

关 键 词：磁性能 烧结温度 居里温度 

分 类 号：TB64[一般工业技术—制冷工程]