| 1. |
- Sahlberg, Martin, 1981-, et al.
(författare)
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Fully reversible hydrogen absorption and desorption reactions with Sc(Al1-xMgx), x=0.0, 0.15, 0.20
- 2011
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Ingår i: Journal of Solid State Chemistry. - : Elsevier BV. - 0022-4596 .- 1095-726X. ; 184:1, s. 104-108
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Tidskriftsartikel (refereegranskat)abstract
- The hydrogen storage properties of Sc(Al1−xMgx), x=0.0, 0.15, 0.20, have been studied by X-ray powder diffraction, thermal desorption spectroscopy, pressure-composition-isotherms and scanning electron microscopy techniques. Hydrogen is absorbed from the gas phase at 70 kPa and 400 °C under the formation of ScH2 and aluminium with magnesium in solid solution. The reaction is fully reversible in vacuum at 500 °C and shows the hydrogenation–disproportionation–desorption-recombination (HDDR) behaviour. The activation energy of desorption was determined by the Kissinger method to 185 kJ/mol. The material is stable up to at least six absorption–desorption cycles and there is no change in particle size during cycling.
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| 2. |
- Sahlberg, Martin, et al.
(författare)
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Structure and hydrogen storage properties of the hexagonal Laves phase Sc(Al1-xNix)2
- 2012
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Ingår i: Journal of Solid State Chemistry. - : Elsevier BV. - 0022-4596 .- 1095-726X. ; 196, s. 132-137
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Tidskriftsartikel (refereegranskat)abstract
- The crystal structures of hydrogenated and unhydrogenated Sc(Al 1-xNi x) 2 Laves phases have been studied by combining several diffraction techniques and it is shown that hydrogen is situated interstitially in the A 2B 2-sites, which have the maximum number of scandium neighbours. The hydrogen absorption/desorption behaviour has also been investigated. It is shown that a solid solution of hydrogen forms in the mother compound. The hydrogen storage capacity exceeds 1.7 H/f.u. at 374 K, and the activation energy of hydrogen desorption was determined to 4.6 kJ/mol H 2. It is shown that these compounds share the same local coordination as Frank-Kasper-type approximants and quasicrystals, which opens up the possibility of finding many new hydride phases with these types of crystal structures.
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