Crystal structure, magnetic and magnetocaloric properties of aluminum-doped La0.6Sr0.4MnO3 perovskites

Abstract

In this paper, we report on the structural, magnetic and magnetocaloric properties of a series of nanocrystallines La 0.6 Sr 0.4 Mn 1-x Al x O 3 (0 B x B 0.2) which were prepared by the sol-gel method. The X-ray powder diffraction showed that all our synthesized samples were of a single phase and have crystallized in the hexagonal symmetry with R 3c space group. Magnetic measurements showed that the sample exhibits a ferromagnetic-to-paramagnetic phase transition at a Curie temperature close to 206 K. The maximum value of the magnetic entropy change DS max M was found to be 1.09 J kg -1 K -1 for an applied magnetic field of 5T. At this value of magnetic field, the relative cooling power was 141 J kg -1 . Our result on magnetocaloric properties suggests that La 0.6 Sr 0.4 Mn 1-x Al x O 3 nanopowder with (0 B x B 0.2) is attractive as a potential refrigerant for high-temperature magnetic refrigeration.