The Variation of Magnetic Entropy on ${\rm Ba}_{2-{\rm x}}{\rm La}_{\rm x}{\rm FeMoO}_{6}$ Compound With the Sintering Temperature

The magnetic entropy behavior has been analyzed in the double-perovskite Ba_2-xLa_xFeMoO₆ (x = 0, 0.1, 0.2) compound with the sintering temperature. Samples were fabricated by conventional solid-state reaction method. The results show that the values of ΔS_M are increased with increasing sintering temperature from 1273 K to 1473 K. The values of ΔS_M for Ba_2-xLa_xFeMoO₆(x = 0) are increased about five times with increasing sintering temperature, especially. The enhancement of the magnetic entropy change is believed to be due to a strong coupling between spin and lattice in the magnetic transition process near Curie temperature. Our result reveals that the proper sintering of perovskite Ba_2-xLa_xFeMoO₆ compound makes it one of the useful methods for the development of advanced magnetic refrigeration materials.