A study of structural, magnetic and magnetocaloric properties of (1−x)La0.6Ca0.4MnO3/xMn2O3 composite materials

•The impact of Mn2O3 secondary phase on the morphology, and physical properties of La0.6Ca0.4MnO3 material was investigated.•When Mn2O3 is mixed with the La0.6Ca0.4MnO3 compound, SEM micrographs show an increase in the grains size.•The Mn2O3 addition has no impact on the Curie temperature of the composites.•For 20% of Mn2O3, the refrigerant capacity can be enhanced by more than 20% when compared to that shown by the mother compound. Perovskite manganite (1−x)La0.6Ca0.4MnO3/xMn2O3 (x = 0, 0.05. 0.1, 0.15, 0.20) composites were prepared by solid state reaction method. X-ray diffraction measurements were used to confirm the crystal structure and the average crystallite size of the samples. Their magnetic, magnetocaloric and heat capacity properties display a presence of second order magnetic phase transition at 260 K. The maximum magnetic entropy change was found to be 5.33 J/kgK for x = 0.1 of Mn2O3 under 5 T. The relative cooling power (RCP) was found (235 J/kg) to largely exceed that reported in early works for a similar family of materials. In addition, the RCP of the mother alloy is enhanced by more than 20% under 32 kOe without affecting the Curie temperature that remains approximately constant close to 260 K. Our results suggest that the addition of Mn2O3 could be useful for the enhancement of the LCMO refrigerant capacity without affecting the Curie temperature.