Room-temperature large magnetocaloric effect in perovskites (La1-xNdx)0.7Sr0.3MnO3

Abstract

Study of the effect of Nd substitution for La on magnetocaloric effect (MCE) of polycrystalline perovskites (La1-xNdx)0.7Sr0.3MnO3 (x = 0.0, 0.2 , 0.4, 0.6, 0.8, 1.0 ) is presented. Large MCE is observed in all samples. The presence of Nd affects to both maximum magnetic entropy change, | Sm|max, and Curie temperature, TC. | Sm|max slightly reduces with low content and increases with high content of Nd and gets maximum value of 4.83 J/kg.K for x = 0.8. TC of the samples determined from the thermomagnetic curves somewhat increases from 346 K for x = 0.0 to 350 K for x = 0.2, then decreases to 235 K for x = 1.0. The sample with x = 0.4 exhibiting the largest value of 74 J/kg for the relative cooling power among the studied samples has TC = 325 K, i.e. higher than room temperature. Our studied samples are promising materials for magnetic refrigerants in the room-temperature region.