摘要
Nanosized (La0.47 Gd0.2)Sr0.33MnO3 perovskite oxides were prepared at relatively low calcinating temperature of 600℃ and 800℃ for 10h using amorphous complex precursor. Curie temperatureTc 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 (La0.47 Gd0.2)Sr0.33MnO3 is a suitable material as working substance in magnetic refrigeration in room temperature.
Nanosized (La_(0.47) Gd_(0.2))Sr_(0.33)MnO_3 perovskite oxides were prepared at relatively low calcinating ~temperature of ~600℃ and ~800℃ for ~10h using amorphous complex precursor. Curie temperature^(T_c) 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 T_c 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 (La_(0.47) Gd_(0.2))Sr_(0.33)MnO_3 is a suitable material as working substance in magnetic refrigeration in room temperature.
出处
《中国有色金属学会会刊:英文版》
CSCD
2005年第3期542-547,共6页
Transactions of Nonferrous Metals Society of China
基金
Projects(50172048
10374090)supportedbytheNationalNaturalScienceFoundationofChina
Project(2002Z020)supportedbytheTalentFoundationofAnhuiProvince
Project(01044906)supportedbytheScienceFoundationofAnhuiProvince,China
关键词
化学合成
纳米结构材料
磁热效应
磁熵交换
钙钛水锰矿
chemical synthesis
nanostructure materials
magnetocaloric effect
magnetic entropy change
perovskite manganite