X-ray Spectroscopic Studies of Materials for Nuclear Technology
2011 (English)Doctoral thesis, comprehensive summary (Other academic)
X-ray spectroscopic experiments, including X-ray absorption spectroscopy (XAS), X-ray emission spectroscopy (XES) and resonant inelastic X-ray scattering (RIXS), were performed in a large energy range (60-9000 eV) on a variety of systems, probing different elements and orbitals. The systems can preferably be divided into three groups: Actinides, copper systems and amorphous materials. We studied oxidation states of Pu in PuO2 using a closed-source experimental setup, developed by us, to lower the safety restrictions associated with such experiments. The presence of Pu with higher oxidation state than Pu(IV) was found in polycrystalline PuO2. This is an important finding since Pu with higher oxidation states has higher solubility affecting the safety of a proposed undeground repository of spent nuclear fuel which can eventually be infiltrated by groundwater. In the proposed underground repository the molecular oxygen will vanish at some point due to microbial activity and mineral oxidation. At this stage sulfur is the most important candidate for causing copper corrosion. We studied Cu films and foils exposed to sulfide solutions at both Cu L2,3, Cu K and S L2,3 edges and found for example that S L2,3 XES is useful for distinguishing between different copper sulfides and Cu Kβ XES can be used to identify monovalent Cu compounds. Amorphous, zirconium containing alloys are potentially useful materials for future nuclear reactors. The electronic structure of such materials was also investigated.
Place, publisher, year, edition, pages
Uppsala: Acta Universitatis Upsaliensis , 2011. , 56 p.
Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology, ISSN 1651-6214 ; 874
XAS, XES, RIXS, amorphous, DOS, spectroscopy, actinides, copper, uranium, plutonium
Atom and Molecular Physics and Optics
IdentifiersURN: urn:nbn:se:uu:diva-160362ISBN: 978-91-554-8205-3OAI: oai:DiVA.org:uu-160362DiVA: diva2:451251
2011-12-09, Polhemsalen, Ångströmlaboratoriet, Lägerhyddsvägen 1, Uppsala, 10:15 (English)
de Groot, Frank, Professor
Butorin, Sergei, Docent
List of papers