Structural, magnetic and magnetocaloric properties in perovskite RE2FeCoO6 (RE = Er and Gd) compounds

The mixed ferrite-cobalties RE2FeCoO6 (RE = Er and Gd) compounds were fabricated by the sol-gel method and the crystal structure, microstructure together with the cryogenic magnetic and magnetocaloric properties were systematically investigated. Both compounds are belonging to the Pbnm space group with an orthorhombic perovskite structure. A considerable reversible magnetocaloric effect (MCE) was induced around the RE sublattice ordering temperatures of 2.7 and 4.9 K for Er2FeCoO6 and Gd2FeCoO6, respectively. For the magnetic field change (Delta H) of 0-7 T, Er2FeCoO6 and Gd2FeCoO6 compounds display the maximum magnetic entropy (Delta S-M(max)) of 14.60 and 21.57 J kg(-1)K(-1), the relative cooling power (RCP) produced by the maximum -Delta S-M(max) below a full-width at half-maximum (delta T-FWHM) in Delta S(T) curve of 280.7 and 346.1 J kg(-1), respectively. The present results demonstrated that Gd2FeCoO6 perovskite is considerable for cryogenic magnetic refrigeration.