Magnetic and magnetocaloric properties of perovskite La0.7Sr0.3Mn1−xCoxO3

Abstract In this paper, the magnetic properties and magnetocaloric effect in La 0.7 Sr 0.3 Mn 1− x Co x O 3 prepared by conventional solid state reaction have been studied. The samples have rhombohedra crystal structure as was determined by room temperature X-ray diffraction. From the measurements, it was found that the Curie temperature ( T C ) and magnetic entropy change (Δ S M ) are strongly dependent on the Co content. The Curie temperature was found to be 338, 300 and 260 K for x =0, 0.05 and 0.1, respectively. Although the variation of maximum entropy change shows a similar tendency with T C , the phase transition temperatures were widened and the |Δ S M | max values, under a change of the magnetic field of 15 kOe, amount to −1.36, −1.17 and −0.92 J/kg K for x =0, 0.05 and 0.1, respectively. The results suggest that Mn-site substitution should be used to tailor Curie temperature and achieve large relative cooling power (RCP).