Effect of trivalent rare earth doping on magnetic and magnetocaloric properties of La0.47(Y,Eu)0.2Pb0.33MnO3 manganites

The La0.47Ln0.2Pb0.33MnO3 (Ln=Eu and Y) polycrystalline has been synthesized using the solid state reaction method at high temperature. The X-ray diffraction shows that the materials crystallized in the orthorhombic structure. Magnetization measurements versus temperature in a magnetic applied field of 0.05 T show that all our samples exhibit a paramagnetic-ferromagnetic transition with decreasing temperature. The value of the Curie temperatures are 275 K and 264 K for Ln=Eu and Y, respectively. The magnetic entropy change reaches a peak (−ΔSmmax) also decreases from 3.31 J/kg. K for Ln=Eu to 2.97 J/kg. K for Ln=Y, and the corresponding values of relative cooling power (RCP) reach 243.25 and 178.88 J/kg, under a magnetic field of 5 T. The results suggest that those polycrystalline could be useful for magnetic refrigeration in a broad temperature range.