α-MnO2 Nanorods’ Magnetocaloric Effect for Hydrogen Liquefaction

The magnetocaloric (MC) effect of α-MnO2 nanorods is predicted using a phenomenological model. The magnetization vs. temperature simulation results were used to obtain the MC characteristics of α-MnO2 nanorods. The magnetic entropy change has a full-width at half-maximum of more than 30 K, providing a good solid base for running the α-MnO2 nanorods in the magnetic refrigerator (MR). Because α-MnO2 nanorods can be used as an effective MC material for MR at temperatures below 50 K, we conclude that the α-MnO2 nanorods could indeed act as a desirable MC magnet inside the MR for space applications, hydrogen liquefaction, and cryocoolers based on the current state of results.