La0.8-xNdxNa0.2MnO3的磁卡效应研究

La_0.8-xNd_xNa_0.2MnO₃的磁卡效应研究

摘要: 用溶胶-凝胶法制备系列样品La_0.8-xNd_xNa_0.2MnO₃(x=0.00,0.05,0.10,0.15和0.20)钙钛矿锰氧化物。研究温度范围在240～340 K、外磁场0～1T下该系列样品的居里温度和磁熵变。发现样品的居里温度TC随x增加而减小,而且x=0.20、温度为295K时,最大磁熵变ΔS_M为1.68 J/kg.K。实验结果表明钙钛矿锰氧化物La_0.8-xNd_xNa_0.2MnO₃有可能作为室温下的磁致冷材料的候选者。

Abstract: Doped perovskite manganites La_0.8-xNd_xNa_0.2MnO₃（x=0.00,0.05,0.10,0.15 and 0.20） were prepared by the sol-gel method.Investigations of Curie Temperature and magnetic entropy change were carried out in the temperature range of 240-340 K and magnetic field range of 0-1T.It is found that the Curie Temperature T_C decreases with increasing x,and the maximum magnetic entropy change ΔS_M（1.68 J/kg·K） is obtained for x=0.20 near the temperature 295 K.The results show that these perovskite manganites have some potential applications for magnetic refrigeration at room temperature.