Large reversible magnetocaloric effect in spinel MnV2O4 with minimal Al substitution

Magnetocaloric effect of MnV1.95Al0.05O4 was studied by the magnetization and heat capacity measurements. MnV1.95Al0.05O4 is a cubic spinel structure with ferromagnetism of second order in nature and performs reversible magnetic entropy around the magnetic transition temperature. The large magnetic entropy changes −ΔSM∼5.2 and 8.2 J/kg K and the adiabatic temperature changes ΔTad∼1.5 and 2.6 K are revealed for the magnetic field changes of 2 and 4 T near the Curie temperature (TC) of 59.6 K, respectively. The relative cooling power (RCP) are about 82.2 and 177.2 J/kg K for magnetic field changes 2 and 4 T, respectively. Compared with the parent compound, although the −ΔSM and ΔTad become smaller, the refrigeration working temperature span and the RCP have been improved.

▸ Large reversible magnetocaloric effect is studied by the magnetization and heat capacity measurements. ▸ The minimal Al substitution can improve the refrigeration working temperature span and the RCP. ▸ Candidate for magnetic refrigerant materials.