Microwave Assisted Hydrothermal Synthesis and Magnetocaloric Properties of La_(0.67)Sr_(0.33)MnO_3 Manganite

摘要

We report microwave assisted hydrothermal synthesis and magnetocaloric properties of La_(0.67)Sr_(0.33)MnO_3 manganite. The synthesized La_(0.67)Sr_(0.33)MnO_3 nanoparticles was characterized using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDS) and magnetization measurements. The XRD results indicated that La_(0.67)Sr_(0.33)MnO_3 nanoparticles have polycrystalline nature with monoclinic structure. FE-SEM results suggested that La_(0.67)Sr_(0.33)MnO_3 nanoparticles are assembled into rod like morphology. Magnetization measurements show that La_(0.67)Sr_(0.33)MnO_3 nanoparticles exhibit transition temperature (T_c) above room temperature. The maximum magnetic entropy change (ΔS_M)~(max) was found to be 0.52 J/kg K near T_c ～ 325 K at applied magnetc field of 20 kOe. This compound may considered as potential material for magnetic refrigeration near room temperature.