Study of Magnetocaloric Effect and Magnetic Phase Transition of Electron-Doped La0.9Sb0.1MnO3 Manganite

An electron-doped La0.9Sb0.1MnO3 manganite was prepared by a sol-gel method, and its magnetocaloric effect and magnetic phase transition (MPT) have been systematically studied. The X-ray diffraction pattern is consistent with the rhombohedral lattice structure (R (3) over barC space group). This sample shows a ferromagnetic order at T-C = 248 K. A maximum magnetic entropy change (-Delta SM max) of 4.79 J kg(-1) K-1 and a relative cooling power (RCP) of 258.15 J kg(-1) are observed at a magnetic field change of 5 T. It is found that the values of -Delta SM max are comparable to some hole-doped manganese compounds. Nevertheless, RCP values of La0.9Sb0.1MnO3 are higher than those of some hole-doped manganites under the same field change, which is very beneficial for designing the magnetic refrigeration materials in engineering. Furthermore, Arrott plots reveal a second-order MPT for La0.9Sb0.1MnO3, which is also confirmed by Franco's universal curves. In addition, the experimental observed -Delta SM follows Lauder's mean-field theory very well, which demonstrates that the magneto-elastic and magneto-electronic couplings have a crucial importance on the magnetic entropy change of La0.9Sb0.1MnO3 manganite.