In situ X-ray diffraction under H2 of the pseudo-AB2 compounds: YNi3.5Al0.5Mg
Language
en
Article de revue
This item was published in
International Journal of Hydrogen Energy. 2008, vol. 33, n° 8, p. 2053-2058
Elsevier
English Abstract
The hydrogenation and dehydrogenation behaviours of the YNi3.5Al0.5Mg compound were studied by in situ X-ray diffraction under hydrogen pressure and at room temperature. The changes of (i) the lattice parameters, (ii) the ...Read more >
The hydrogenation and dehydrogenation behaviours of the YNi3.5Al0.5Mg compound were studied by in situ X-ray diffraction under hydrogen pressure and at room temperature. The changes of (i) the lattice parameters, (ii) the crystallite size and (iii) the lattice strain during the sorption process (i.e. along the PC isotherms) were studied. These results indicate that the crystallite size decreases by a factor of 2. The micro deformations increase at first and then tend to almost zero at the end of the sorption cycle. This behaviour is explained in terms of co-existence of the metal (i.e. greek small letter alpha phase) and metal hydride (i.e. β phase) phases. The change in crystallinity is consistent with the hydrogen induced amorphisation process existing in a lot of AB2 compounds. No anisotropic effects can be highlighted on this pseudo-AB2 compounds in contrary with what could be observed in AB5 compounds.Read less <
Origin
Hal imported