Abstract
Hydrogenation properties of MmNi4.30 - x Cox Al0.30 Mn0.40 (x = 0, 0.75) were investigated by means of in situ X-ray diffraction (XRD). The XRD profiles were analyzed by the Rietveld method to evaluate the change of lattice parameters and lattice volume. Hydrogenation-dehydrogenation of these alloys proceeded through two phases between the solid solution phase and the hydride phase. Both the phases of MmNi4.30Al0.30Mn0.40 had the hexagonal lattice with a space group of P6/mmm and those of MmNi3.55Co0.75Al0.30Mn0.40 had the orthorhombic lattice with Cmmm after initial activation. In the two-phase co-existing region, lattice volumetric ratio of both the phases showed 19% for MmNi4.30Al0.30Mn0.40, while that became 10% by partial substitution of Co for Ni with anisotropic lattice expansion. Anisotropic lattice strain related with high dislocation density was not introduced through formation of the hydride phase.
Original language | English |
---|---|
Pages (from-to) | 3435-3441 |
Number of pages | 7 |
Journal | International Journal of Hydrogen Energy |
Volume | 32 |
Issue number | 15 SPEC. ISS. |
DOIs | |
Publication status | Published - Jan 1 2007 |
All Science Journal Classification (ASJC) codes
- Renewable Energy, Sustainability and the Environment
- Fuel Technology
- Condensed Matter Physics
- Energy Engineering and Power Technology