Giant magnetic entropy change in manganese perovskite La0.67Sr0.16Ca0.17MnO3 near room temperature

Structural, magnetic and magnetocaloric properties of La0.67Sr0.16Ca0.17MnO3 perovskite have been studied. A solid state reaction method was used in the preparation phase. X-ray diffraction analysis using Rietveld refinement revealed that this sample crystallizes in the distorted rhombohedral system with
R 3c space group. The variation of magnetization (M) vs. temperature (T), under an applied magnetic field of 0.05T, revealed a transition from a ferromagnetic (FM) to paramagnetic (PM) phase at around Curie temperature (TC = 336 K). Using Arrott plots, it was found that the transition is of a second-order. Isothermal measurements of magnetization allow us, through thermodynamic Maxwell relations, to determine the magnetic entropy change (DSM). A large DSM deduced from isothermal magnetization curves, has been observed in our sample with a peak centered around its respective TC. The maximum of the magnetic entropy change DSmax M in a magnetic field change of 5T is found to be 5.51Jkg 1K 1 at 335K. In addition, the compound showed a large relative cooling power (RCP) value of about 234 J/kg while the maximum refrigerant capacity of 174 J/kg was attained at the applied field of 5T. As a result, the studied sample can be considered as a potential material for magnetic refrigeration.