uu.seUppsala University Publications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Fully reversible hydrogen absorption and desorption reactions with Sc(Al1-xMgx), x=0.0, 0.15, 0.20
Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Inorganic Chemistry.
Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Inorganic Chemistry.
2011 (English)In: Journal of Solid State Chemistry, ISSN 0022-4596, E-ISSN 1095-726X, Vol. 184, no 1, 104-108 p.Article in journal (Refereed) Published
Abstract [en]

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.

Place, publisher, year, edition, pages
2011. Vol. 184, no 1, 104-108 p.
Keyword [en]
Scandium intermetallics, Hydrides, Hydrogen storage materials, X-ray diffraction
National Category
Inorganic Chemistry
Research subject
Chemistry with specialization in Inorganic Chemistry
Identifiers
URN: urn:nbn:se:uu:diva-107388DOI: 10.1016/j.jssc.2010.10.034ISI: 000286774600015OAI: oai:DiVA.org:uu-107388DiVA: diva2:229060
Available from: 2009-08-11 Created: 2009-08-10 Last updated: 2017-12-13Bibliographically approved
In thesis
1. Light-Metal Hydrides for Hydrogen Storage
Open this publication in new window or tab >>Light-Metal Hydrides for Hydrogen Storage
2009 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Demands for zero greenhouse-gas emission vehicles have sharpened with today’s increased focus on global warming. Hydrogen storage is a key technology for the implementation of hydrogen powered vehicles. Metal hydrides can claim higher energy densities than alternative hydrogen storage materials, but a remaining challenge is to find a metal hydride which satisfies all current demands on practical usability. Several metals store large amounts of hydrogen by forming a metal hydride, e.g., Mg, Ti and Al. The main problems are the weight of the material and the reaction energy between the metal and hydrogen.

Magnesium has a high storage capacity (7.6 wt.% hydrogen) in forming MgH2; this is a slow reaction, but can be accelerated either by minimizing the diffusion length within the hydride or by changing the diffusion properties. Light-metal hydrides have been studied in this thesis with the goal of finding new hydrogen storage compounds and of gaining a better understanding of the parameters which determine their storage properties. Various magnesium-containing compounds have been investigated. These systems represent different ways to address the problems which arise in exploiting magnesium based materials. The compounds were synthesized in sealed tantalum tubes, and investigated by in situ synchrotron radiation X-ray powder diffraction, neutron powder diffraction, isothermal measurements, thermal desorption spectroscopy and electron microscopy.

It is demonstrated that hydrogen storage properties can be improved by alloying magnesium with yttrium or scandium. Mg-Y-compounds decompose in hydrogen to form MgH2 nano-structures. Hydrogen desorption kinetics are improved compared to pure MgH2. The influence of adding a third element, gallium or zinc has also been studied; it is shown that gallium improves hydrogen desorption from YH2. ScAl1-xMgx is presented here for the first time as a hydrogen storage material. It absorbs hydrogen by forming ScH2 and Al(Mg) in a fully reversible reaction. It is shown that the hydrogen desorption temperature of ScH2 is reduced by more than 400 °C by alloying with aluminium and magnesium.

Place, publisher, year, edition, pages
Uppsala: Acta Universitatis Upsaliensis, 2009. 56 p.
Series
Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology, ISSN 1651-6214 ; 666
Keyword
Metal-hydrogen compounds, hydrides, hydrogen storage, X-ray diffraction, neutron diffraction, thermal desorption spectroscopy
National Category
Chemical Sciences Inorganic Chemistry
Research subject
Inorganic Chemistry
Identifiers
urn:nbn:se:uu:diva-107380 (URN)978-91-554-7585-7 (ISBN)
Public defence
2009-09-25, Häggsalen, Ångströmlaboratoriet, Lägerhyddsvägen 1, Uppsala, 10:15 (English)
Opponent
Supervisors
Available from: 2009-09-04 Created: 2009-08-10 Last updated: 2009-09-04Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full text

Authority records BETA

Sahlberg, MartinAndersson, Yvonne

Search in DiVA

By author/editor
Sahlberg, MartinAndersson, Yvonne
By organisation
Inorganic Chemistry
In the same journal
Journal of Solid State Chemistry
Inorganic Chemistry

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 917 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf