Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • 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
Oxidation of plutonium dioxide
KTH, Superseded Departments, Materials Science and Engineering.ORCID iD: 0000-0002-9920-5393
KTH, Superseded Departments, Materials Science and Engineering.ORCID iD: 0000-0003-2832-3293
KTH, Superseded Departments, Materials Science and Engineering.
KTH, Superseded Departments, Materials Science and Engineering.
2004 (English)In: Nature Materials, ISSN 1476-1122, E-ISSN 1476-4660, Vol. 3, no 4, 225-228 p.Article in journal (Refereed) Published
Abstract [en]

The physics and chemistry of the actinide elements form the scientific basis for rational handling of nuclear materials(1-3). In recent experiments(4), most unexpectedly, plutonium dioxide has been found to react with water to form higher oxides up to PuO2.27, whereas PuO2 had always been thought to be the highest stable oxide of plutonium(2,3). We perform a theoretical analysis of this complicated situation on the basis of total energies calculated within density functional theory(5,6) combined with well-established thermodynamic data. The reactions of PuO2 with either O-2 or H2O to form PuO2+delta are calculated to be endothermic: that is, in order to occur they require a supply of energy. However, our calculations show that PuO2+delta can be formed, as an intermediate product, by reactions with the products of radiolysis of water, such as H2O2.

Place, publisher, year, edition, pages
2004. Vol. 3, no 4, 225-228 p.
National Category
Other Engineering and Technologies not elsewhere specified Condensed Matter Physics Materials Chemistry
Identifiers
URN: urn:nbn:se:kth:diva-6886DOI: 10.1038/nmat1095ISI: 000220747700015Scopus ID: 2-s2.0-1842630582OAI: oai:DiVA.org:kth-6886DiVA: diva2:11726
Note
QC 20100622Available from: 2007-03-14 Created: 2007-03-14 Last updated: 2012-03-22Bibliographically approved
In thesis
1. From the Electronic Structure of Point Defects to Functional Properties of Metals and Ceramics
Open this publication in new window or tab >>From the Electronic Structure of Point Defects to Functional Properties of Metals and Ceramics
2007 (English)Doctoral thesis, comprehensive summary (Other scientific)
Abstract [en]

Point defects are an inherent part of crystalline materials and they influence important physical and chemical properties, such as diffusion, hardness, catalytic activity and phase stability. Increased understanding of point defects enables us to tailor the defect-related properties to the application at hand. Modeling and simulation have a prominent role in acquiring this knowledge. In this thesis thermodynamic and kinetic properties of point defects in metals and ceramics are studied using first-principles calculations based on density functional theory. Phenomenological models are used to translate the atomic level properties, obtained from the first-principles calculations, into functional materials properties. The next paragraph presents the particular problems under study.

The formation and migration of vacancies and simple vacancy clusters in copper are investigated by calculating the energies associated with these processes. The structure, stability and electronic properties of the low-oxygen oxides of titanium, TiOx with 1/3 < x < 3/2, are studied and the importance of structural vacancies is demonstrated. We develop an integrated first-principles and Calphad approach to calculate phase diagrams in the titanium-carbon-nitrogen system, with particular focus on vacancy-induced ordering of the substoichiometric

carbonitride phase, TiCxNy (x+y < 1). The possibility of forming higher oxides of plutonium than plutonium dioxide is explored by calculating the enthalpies for nonstoichiometric defect-containing compounds and the analysis shows that such oxidation is only produced by strong oxidants. For ceria (CeO2) doped with trivalent ions from the lanthanide series we probe the connection between the choice of a dopant and the improvement of ionic conductivity by studying the oxygen-vacancy formation and migration properties. The significance of minimizing the dopant-vacancy interactions is highlighted. We investigate the redox thermodynamics of CeO2-MO2 solid solutions with M being Ti, Zr, Hf, Th, Si, Ge, Sn or Pb and show that reduction is facilitated by small solutes.

The results in this thesis are relevant for the performance of solid electrolytes, which are an integral part of solid oxide fuel cells, oxygen storage materials in automotive three-way catalysts, nuclear waste materials and cutting tool materials.

Place, publisher, year, edition, pages
Stockholm: Materialvetenskap, 2007
Keyword
first principles, ab initio, density functional theory, Calphad, point defects, diffusion, solid electrolytes, oxygen storage materials
National Category
Other Engineering and Technologies not elsewhere specified
Identifiers
urn:nbn:se:kth:diva-4309 (URN)978-91-7178-590-9 (ISBN)
Public defence
2007-03-30, F2, Lindstedtsvägen 26, Stockholm, 10:00
Opponent
Supervisors
Note
QC 20100622Available from: 2007-03-14 Created: 2007-03-14 Last updated: 2012-03-22Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textScopus

Authority records BETA

Korzhavyi, Pavel A.Vitos, Levente

Search in DiVA

By author/editor
Korzhavyi, Pavel A.Vitos, LeventeAndersson, David A.Johansson, Börje
By organisation
Materials Science and Engineering
In the same journal
Nature Materials
Other Engineering and Technologies not elsewhere specifiedCondensed Matter PhysicsMaterials Chemistry

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 129 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • 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