用溶胶-凝胶法制备了不同空位掺杂的系列样品La0.7-xCa0.28Sr0.02MnO3,研究了La3+空位浓度对样品居里温度和磁热效应的影响.结果表明,在La位掺入少量空位(x＜0.06),可以实现将样品的居里温度有效调整至室温,同时也促进了样品磁熵变的提高.当La空位掺杂x=0.06时,与未空位掺杂样品相比,居里温度由227 K提高到264 K,近室温,其磁熵变值为3.01 J· kg-1·K-1(外加磁场1T).该系列样品在室温附近,较低磁场下,有较强的磁制冷能力.
参考文献
| [1] | Haiying Chen;Chin Lin;Daosheng Dai.Magnetocaloric effect in (La,R)_(2/3)Ca_(1/3)MnO_3 (R=Gd, Dy, Tb, Ce)[J].Journal of Magnetism and Magnetic Materials,20032/3(2/3):254-257. |
| [2] | W. Chen;L.Y. Nie;W. Zhong.Magnetocaloric effect in Nd doped perovskite La_(0.7-x)Nd_xBa_(0.3)MnO_3 polycrystalline near room temperature[J].Journal of Alloys and Compounds: An Interdisciplinary Journal of Materials Science and Solid-state Chemistry and Physics,20051/2(1/2):23-25. |
| [3] | M.-H. Phan;S.C. Yu;N.H. Hur.Magnetic and magnetocaloric properties of (La_(1-x))_(0.8)Ca_(0.2)MnO_3 (x =0.05, 0.20) single crystals[J].Journal of Magnetism and Magnetic Materials,20033(3):407-411. |
| [4] | G.C. Lin;Q. Wei;J.X. Zhang.Direct measurement of the magnetocaloric effect in La_(0.67)Ca_(0.33)MnO_3[J].Journal of Magnetism and Magnetic Materials,20062(2):392-396. |
| [5] | 陈伟;钟伟;都有为;潘成福;常虹.La0.8-xCa0.2MnO3纳米颗粒的居里温度与磁热效应[J].物理学报,2001(2):319-323. |
| [6] | W. Zhong;W. Chen.Synthesis,structure and magnetic entropy change of polycrystalline La1-xKxMnO3+δ[J].Journal of Magnetism and Magnetic Materials,19991(1):112-118. |
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