Structural, magnetic and magnetocaloric properties of La0.6Ca0.4Mn1−xFexO3 (x=0, 0.05, 0.1, 0.15 and 0.2) manganites

The effect of Fe on the microstructure, magnetic and magnetocaloric properties has been investigated in the La0.6Ca0.4Mn1−xFexO3 ( 0 ≤ x ≤ 0.2 ) manganite compounds. X-ray diffraction reveals that all the samples crystallize in a rhombohedral structure (space group R 3 ¯ c ) and that the introduction of iron does not affect the lattice parameters and structural symmetry. With the increasing Fe content, the Curie temperature T C decreases from 275 K (x=0) to 75 K (x=0.2). Temperature dependences of the magnetization in both field cooled and zero field cooled modes show the coexistence of ferromagnetic and antiferromagnetic interactions for x ≥ 0.1 . The maximum entropy change Δ S M exhibits a decrease from 5.2 J/kg K for x=0 to 0.2 J/kg K for x=0.2 under an applied magnetic field change of 5 T. The highest relative cooling power was found to be equal to 270 J/kg for x=0.05, suggesting that La0.6Ca0.4Mn0.95Fe0.05O3 may be a suitable candidate for magnetic refrigeration.