Thermodynamic properties of MgFeH3 alloy

Abstract

The main objective of this work is to improve the kinetic properties and desorption temperature in MgFeH3 by applying different pressures. The first principles study was used for this purpose using the WIEN2k code, and all the calculations proceeded without a spin channel. We have theoretically determined that MgFeH3 has 3.64 wt. % gravimetric hydrogen storage capacity. The cubic crystal structure significantly improves the formation energy as well as desorption temperature at higher pressures. Phonon dispersion curves predict that the stability of the compound decreases with increasing pressures. At the same time, DOS shows that d-states of Fe move from valence to conduction band with increasing pressures. In thermodynamic properties, we have calculated entropy, specific heat at constant pressure (Cp), thermal expansion coefficient (