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
Resonant inelastic X-ray scattering and X-ray absorption spectroscopy on the cathode materials LiMnPO4 and LiMn0.9Fe0.1PO4: A comparative study
Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Soft X-Ray Physics.
Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Structural Chemistry.
Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Structural Chemistry.
Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Soft X-Ray Physics.
2011 (English)In: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 13, no 45, 20215-20222 p.Article in journal (Refereed) Published
Abstract [en]

We present a study of the charge-state behavior of the Li-ion battery cathode materials LixMnPO4 and LixMn0.9Fe0.1PO4 usingx-ray absorption spectroscopy (XAS) and resonant inelastic x-ray scattering (RIXS). A set of six identical battery cathodesfor each material have been cycled and left in different charge states in the range of x=0.2...1.0 before disassembly in an Arglove box. Unexpectedly, we find that the Mn 3d-bands are almost inert to the delithiation process, suggesting that Mn ionsparticipate to a very small extent in the charge compensation process. In LixMn0.9Fe0.1PO4 the Fe 3d-band shows much moreresponse to delithiation than the Mn 3d-band. The O 2p-band hybridizes with the bands of the other ions in LixMnPO4 and LixMn0.9Fe0.1PO4 and thus, indirectly, carries useful information about the effects of delithiation at all ion sites. We conclude,that the redox reactions during lithiation/delithiation of these materials are complex and involve repopulation of charges for allconstituent elements.

Place, publisher, year, edition, pages
Cambridge, UK: RCS Publishing , 2011. Vol. 13, no 45, 20215-20222 p.
Keyword [en]
Valence number, X-ray spectroscopy, Li-ion battery, RIXS
National Category
Atom and Molecular Physics and Optics Inorganic Chemistry
Research subject
Physics with spec. in Atomic, Molecular and Condensed Matter Physics; Chemistry with specialization in Inorganic Chemistry
Identifiers
URN: urn:nbn:se:uu:diva-149320DOI: 10.1039/c1cp20673gISI: 000296871500024OAI: oai:DiVA.org:uu-149320DiVA: diva2:404539
Available from: 2011-03-17 Created: 2011-03-17 Last updated: 2011-12-13Bibliographically approved
In thesis
1. Redox Reactions in Li-ion Battery Cycling and in Cu Corrosion Studied by Soft X-ray Spectroscopy
Open this publication in new window or tab >>Redox Reactions in Li-ion Battery Cycling and in Cu Corrosion Studied by Soft X-ray Spectroscopy
2011 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The topic of this thesis is redox reactions in two technologically important contexts: firstly, in Li-ion battery electrodes during cycling, and secondly, in copper corrosion in oxygen-free ground water containing sulfide. In an attempt to expand the understanding of the charge uptake process in battery electrodes and the chemical reactions on copper surfaces upon sulfide exposure, soft X-ray spectroscopy has been used to study the electronic structure of these systems.

To ascertain the changes in electron density at different atomic sites in a battery electrode material, both X-ray absorption spectroscopy (XAS) and resonant inelastic X-ray scattering (RIXS) have been applied to different electrode materials. This thesis explains in detail the assembling procedure, cycling, and situ sample preparation of the battery materials. Furthermore, two different designs used in in situ experiments for study of batteries during cycling are also discussed.

The main result from the Li-ion battery materials is the justification to abandon the view of valences as integers. This is true for all battery electrodes examined in this thesis. Generally, oxygen plays a more important role in the charge uptake than commonly assumed, but also the transition metals and other species apart from expected behavior. In LiMnPO4, even the notion of Li as strictly Li+ must be questioned.

Copper is intended to act as a corrosion barrier in a nuclear waste repository. In the corrosion experiments presented in this thesis, different copper oxides were exposed to the conditions present at the planned repository site, with exception for the concentration of sulfide, which was greatly increased.

The conclusion from these experiments is that sulfide effectively reduces Cu(II) oxide to Cu(I) compounds and possibly forms a compound containing both oxygen and sulfur. Also, the thickness and inhomogeneity of the copper oxide surface layers are of great importance for the corrosion mechanisms, including passivation.

Place, publisher, year, edition, pages
Uppsala: Acta Universitatis Upsaliensis, 2011. 69 p.
Series
Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology, ISSN 1651-6214 ; 812
National Category
Physical Sciences
Identifiers
urn:nbn:se:uu:diva-148396 (URN)978-91-554-8036-3 (ISBN)
Public defence
2011-05-06, room 2001, Ångströmlaboratoriet, Lägerhyddsvägen 1, Uppsala, 13:15 (English)
Opponent
Supervisors
Available from: 2011-04-14 Created: 2011-03-05 Last updated: 2011-05-05Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full text

Authority records BETA

Hollmark, HåkanGustafsson, TorbjörnEdström, KristinaDuda, Laurent-C.

Search in DiVA

By author/editor
Hollmark, HåkanGustafsson, TorbjörnEdström, KristinaDuda, Laurent-C.
By organisation
Soft X-Ray PhysicsStructural Chemistry
In the same journal
Physical Chemistry, Chemical Physics - PCCP
Atom and Molecular Physics and OpticsInorganic Chemistry

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 1141 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