中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 15 No. 3 June 2005 |
（1. College of Engineering, Zhanjiang Ocean University, Zhanjiang 524088, China;
2. Institute of Solid State Physics, Chinese Academy of Sciences,
Hefei 230031, China）
Abstract:Nanosized (La0.47Gd0.2)Sr0.33MnO3 perovskite oxides were prepared at relatively low calcinating temperature of 600℃ and 800℃ for 10h using amorphous complex precursor. Curie temperature(Tc) and magnetocaloric effects(MCE) were investigated. X-ray diffraction(XRD) and electron diffraction(ED) reveal that the resulting products are of pure single-phase rhombohedral perovskite structure. Transmission electron microscopy(TEM) observation finds that the particle sizes are about 40-50nm and 80-100nm, and the Tc are 285.1K and 285.9K, MCE are about 2.02J/(kg•K-1) and 3.90J/(kg•K-1) at 5T magnetic field. A relatively large MCE with a broad peak around Curie temperature is observed in sample sintered at 800℃ for 10h. This suggests that nanosized (La0.47Gd0.2)Sr0.33MnO3 is a suitable material as working substance in magnetic refrigeration in room temperature.
Key words: chemical synthesis; nanostructure materials; magnetocaloric effect; magnetic entropy change; perovskite manganite
