Hydrogen storage (HS) performance of three Mg-xIn-yCB alloys (CB – amorphous carbon, x = 55, 64, 73; y = 10 wt%) was studied. Indium concentration covered an area of ordered structures. Alloys were prepared by ball-milling in hydrogen atmosphere. Kinetic curves and PCT isotherms were measured in the temperature interval from 200 °C to 325 °C. X-ray diffraction spectroscopy (XRD) was used for structure investigation. Alloy with x = 73 wt% In (’’ structure) showed reversible amorphization during temperature cycling between about 100 °C and 350 °C. Hydrogen sorption experiments were done by the Sieverts method under the hydrogen gas pressure ranging from 0.1 MPa to 2.5 MPa. It was found that hydrogen sorption capacity varied between 0.47 and 1.1 wt% H2. Hydride formation enthalpy H calculated from desorption PCT experiments was significantly lower than H, known for pure Mg. This invoked an idea that atomic order of Mg-based HS materials might decrease the high thermodynamic stability of hydride phase.Keywords: Hydrogen storage, Mg alloys, hydride stability, ordering
© This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.