Hydrogen sorption properties of new magnesium intermetallic compounds with MgSnCu₄ type structure

A statistical theory of the MgCeCo4-H-2 system has been developed for hydrogenation and phase transitions under pressure. The free energy value is calculated. The equation of thermodynamic equilibrium is obtained. The temperature of the order-disorder phase transition is estimated. Isotherms and Isoplethes of hydrogen absorption-desorption are constructed. The possibility of a hysteresis effect is established. The temperature dependence of the hydrogen solubility is found taking into account the phase transition configuration heat capacity. The calculated and experimental graphs of the sorption isotherm are of a similar nature. (C) 2021 Published by Elsevier Ltd on behalf of Hydrogen Energy Publications LLC.