Significantly decreased stability of MgH2 in the Mg-In-C alloy system: Long-period-stacking-ordering as a new way how to improve performance of hydrogen storage alloys?

0519067 - ÚFM 2021 RIV GB eng J - Článek v odborném periodiku
Čermák, Jiří - Král, Lubomír - Roupcová, Pavla
Significantly decreased stability of MgH2 in the Mg-In-C alloy system: Long-period-stacking-ordering as a new way how to improve performance of hydrogen storage alloys?
Renewable Energy. Roč. 150, MAY (2020), s. 204-212. ISSN 0960-1481. E-ISSN 1879-0682
Grant CEP: GA MŠMT(CZ) LQ1601; GA ČR(CZ) GA17-21683S
Institucionální podpora: RVO:68081723
Klíčová slova: Hydrogen storage * Mg alloys * Hydride stability * Ordering
Obor OECD: Materials engineering
Impakt faktor: 8.001, rok: 2020
Způsob publikování: Omezený přístup
https://doi.org/10.1016/j.renene.2019.12.107

Hydrogen storage (HS) performance of Mg-In-CB alloys (CB – amorphous carbon) is studied. Indium concentration covers primary solid solution (Mg), two phase area (Mg) + β1 and also alloys containing ordered β structures. Seven Mg-In-CB alloys are prepared by ball-milling in hydrogen atmosphere. Kinetic curves and PCT isotherms are measured in the temperature interval from 200 °C to 375 °C. Hydrogen sorption experiments are done by the Sieverts method under the hydrogen gas pressure ranging from 0.1 MPa to 2.5 MPa. X-ray diffraction spectroscopy is used for structure investigation. Alloy with β’’ structure shows reversible amorphization during temperature cycling between about 100 °C and 350 °C. It is found that hydrogen sorption capacity varies between about 6 wt % H2 for (Mg) and 0.6 wt % H2 for β’’ structure. Hydride decomposition enthalpy calculated from desorption PCT experiments decreases to 54 ± 3 kJ × (mol H2)−1 and 57 ± 3 kJ × (mol H2)−1 for ordered alloys in the interval from 69 to 71 wt % In, and even down to 51.5 kJ × (mol H2)−1 for amorphous β’’ structure. Activation energy of desorption kinetics is also lowered in the ordered structure.
Trvalý link: http://hdl.handle.net/11104/0309691