uu.seUppsala University Publications
Change search
Refine search result
1 - 45 of 45
CiteExportLink to result list
Permanent 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
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1.
    Andersson, Joakim
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics and Materials Science, Physics II. Materials Science.
    Schmitt, Thorsten
    Department of Physics. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics and Materials Science, Physics II. Materials Science.
    Duda, Laurent
    Department of Physics. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics and Materials Science, Physics II. Materials Science.
    Jacobson, Staffan
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics and Materials Science, Physics II. Materials Science.
    Phase transformations in CVD diamond wear tracks revealed by NEXAFS mapping2004In: Nordtrib 2004, Tromsö, Norway, 2004Conference paper (Refereed)
    Abstract [en]

    The origin of the different Li+ intercalation behavior of raw and jet-milled natural graphite has been investigated. Jet-milled graphite is found to cycle reversibly in equal solvent mixture of propylene carbonate (PC) and etylene carbonate (EC), whereas raw graphite does not. Using both Al Ka and synchrotron radiation (SR) Photoelectron Spectroscopy, new insight is obtained inti the formation of the solid electrolyte interphase (SEI) on the two different graphite materials during electrochemical cycling in 1 M LiPF6 in either PC:EC (1:1) or in PC with 5% vinylene carbonate (VC) as additive. Solvent reduction products are found at the surface of both raw and jat-milled graphite cycled in PC:EC (1:1), but differed in composition. The addition of VC reduces primarily the quantities of salt reaction products (LiF and LixPFy compounds) and produces a mainly organic SEI layer. Electron diffraction from the edges for raw and jet-milled graphite particles shows a physical barrier hindering PC co-intercalation and faciltating the formation of a stable SEI layer.

  • 2.
    Augustsson, A
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Chemistry, Department of Materials Chemistry, Structural Chemistry. Department of Physics and Materials Science, Physics II.
    Schmitt, T
    Duda, L
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Chemistry, Department of Materials Chemistry, Structural Chemistry. Department of Physics and Materials Science, Physics II.
    Nordgren, J
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Chemistry, Department of Materials Chemistry, Structural Chemistry. Department of Physics and Materials Science, Physics II.
    Nordlinder, Sara
    Chemistry, Department of Materials Chemistry, Structural Chemistry. Department of Physics and Materials Science, Physics II. strukturkemi.
    Edström, Kristina
    Chemistry, Department of Materials Chemistry, Structural Chemistry. Department of Physics and Materials Science, Physics II. strukturkemi.
    Gustafsson, Torbjörn
    Chemistry, Department of Materials Chemistry, Structural Chemistry. Department of Physics and Materials Science, Physics II. strukturkemi.
    Guo, J H
    The electronic structure and lithiation of electrodes based on vanadium-oxide nanotubes2003In: Journal of Applied Physics, Vol. 94, no 8, p. 5083-5087Article in journal (Refereed)
    Abstract [en]

    The synthesis of a novel ligand 2′-[1-(2-pyridinyl)-ethylidene]-oxamohydrazide (Hapsox), from a series of 2-acetylpyridine acylhydrazones, and its complex with Co(III), which is the first in this series of complexes are described. Both the ligand and the complex were characterized by elemental analysis, IR, 1H-NMR, and 13C-NMR spectra, and the structure of the complex [Co(apsox)2]ClO4 was determined by X-ray structural analysis. It was established that [Co(apsox)2]ClO4 has an octahedral geometry with two tridentate apsox ligands in monoanionic form. Structural characteristics, lengths of the bonds, and angles between the bonds were typical for Co(III) complexes of distorted octahedral geometry. Both direct and template synthesis afforded the same geometrical isomer of the complex with two apsox ligands meridionally bound to the central metal ion, even in the case when equimolar quantities of Co(ClO4)2 and Hapsox were applied.

  • 3.
    Duda, L
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II. Fysik II.
    Schmitt, T
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II. Fysik II.
    Nordgren, J
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II. Fysik II.
    Dhalenne, G
    Revcolevschi, A
    Resonant inelastic soft X-ray scattering of insulating cuprates2002In: Surface Review and Letters, Vol. 9, no 2, p. 1103-1108Article in journal (Refereed)
  • 4.
    Duda, Laurent C.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics.
    Schmitt, Torsten
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics.
    Magnuson, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics.
    Forsberg, Johan
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics.
    Olsson, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics.
    Nordgren, Joseph
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics.
    Okada, K.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics.
    Kotani, A.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics.
    Reply to comment by Hüfner on "Resonant Inelastic X-Ray Scattering at the Oxygen K Resonance of NiO: Nonlocal Charge Transfer and Double-Singlet Excitations"2006In: Physical Review Letters, ISSN 0031-9007, E-ISSN 1079-7114, Vol. 97, no 269702Article in journal (Other academic)
  • 5.
    Duda, Laurent
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and Condensed Matter Physics.
    Edström, Kristina
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström.
    Oxygen redox reactions in Li ion battery electrodes studied by resonant inelastic X-ray scattering2017In: Journal of Electron Spectroscopy and Related Phenomena, ISSN 0368-2048, E-ISSN 1873-2526, Vol. 221, p. 79-87Article in journal (Refereed)
    Abstract [en]

    We present results using inelastic scattering x-ray spectroscopy (RIXS) combined with x-ray absorption spectroscopy on Li ion battery cathode and anode materials, respectively. In particular, we discuss results obtained on the cathode materials Li1.2[Ni0.13Co0.133Mn0.544]O2 and Lix[Ni0.65Co0.25Mn0.1]O2 as well as in the composite anode material Ni0.5TiOPO4/C. We show that oxygen redox reactions are an important aspect of many such systems and how one can succesfully address them using RIXS. New insights on the formation of new oxygen species and on the details of cycling-induced structural disorder can be detected. We foresee a particular future focus on these issues considering the rapid development of new in operando RIXS techniques for Li ion battery research.

  • 6.
    Duda, Laurent
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II.
    Schmitt, Thorsten
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II.
    Augustsson, Andreas
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II.
    Nordgren, Joseph
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II.
    Resonant soft X-ray emission of solids and liquids2004In: Journal of Alloys and Compounds, Vol. 362, no 1-2, p. 116-123Article in journal (Refereed)
  • 7.
    Duda, Laurent
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics, Physics II.
    Schmitt, Thorsten
    Magnuson, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics, Physics II.
    Forsberg, Johan
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Soft X-Ray Physics.
    Olsson, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics, Physics II.
    Nordgren, Joseph
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics, Physics II.
    Okada, K
    Kotani, A
    Resonant inelastic x-ray scattering at the NiO O K-resonance: non-local charge-transfer and double singlet excitations2006In: Physical Review Letters, ISSN 0031-9007, E-ISSN 1079-7114, Vol. 96, no 6, p. 067402-Article in journal (Refereed)
  • 8.
    Duda, Laurent
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II.
    Schmitt, Thorsten
    Magnuson, Martin
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II.
    Forsberg, Johan
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II.
    Olsson, Anders
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II.
    Nordgren, Joseph
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II.
    Okada, K
    Kotani, A
    Resonant inelastic x-ray scattering at the oxygen K resonance of NiO: Nonlocal charge transfer and double-singlet excitations2006In: Physical Review Letters, Vol. 96, no 6Article in journal (Refereed)
  • 9.
    Duda, Laurent
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II.
    Schmitt, Thorsten
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II.
    Nordgren, Joseph
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II.
    Kuiper, Pieter
    Dhalenne, G
    Revcolevschi, A
    Low-energy excitations in resonant inelastic x-ray scattering of alpha(')-NaV2O52004In: Physical Review Letters, Vol. 93, no 169701Article in journal (Refereed)
  • 10.
    Duda, Laurent
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics.
    Schmitt, Thorsten
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics, Physics II.
    Nordgren, Joseph
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics.
    Kuiper, Pieter
    Dhalenne, Guy
    Revscolevschi, Alexandre
    Low-energy excitations in resonant inelastic X-ray scattering of α' - NaV2O52004In: Physical Review Letters, ISSN 0031-9007, E-ISSN 1079-7114, Vol. 15, no 93, p. 169701-Article in journal (Refereed)
  • 11.
    Gråsjö, Johan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Andersson, Egil
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Forsberg, Johan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Aziz, Emad
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Brena, Barbara
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Johansson, Christian
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Nordgren, Joseph
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Duda, Laurent
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Rubensson, Jan-Erik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Hansson, Per
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Oxygen K-edge studies of water poor surfactant gel systems2008Conference paper (Other (popular science, discussion, etc.))
  • 12.
    Hakim, Charifa
    et al.
    Mohammed VI Polytech Univ, Mat Sci & Nanoengn, Lot 660 Hay Moulay Rachid, Ben Guerir, Morocco;Cadi Ayyad Univ, LCME, Fac Sci & Technol, Av A El Khattabi,PB 549, Marrakech, Morocco.
    Sabi, Noha
    Mohammed VI Polytech Univ, Mat Sci & Nanoengn, Lot 660 Hay Moulay Rachid, Ben Guerir, Morocco;Cadi Ayyad Univ, LCME, Fac Sci & Technol, Av A El Khattabi,PB 549, Marrakech, Morocco.
    Ma, Le Anh
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Dahbi, Mouad
    Mohammed VI Polytech Univ, Mat Sci & Nanoengn, Lot 660 Hay Moulay Rachid, Ben Guerir, Morocco.
    Brandell, Daniel
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Edström, Kristina
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Duda, Laurent
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and Condensed Matter Physics.
    Saadoune, Ismael
    Cadi Ayyad Univ, LCME, Fac Sci & Technol, Av A El Khattabi,PB 549, Marrakech, Morocco.
    Younesi, Reza
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Understanding the redox process upon electrochemical cycling of the P2-Na0.78Co1/2Mn1/3Ni1/6O2 electrode material for sodium-ion batteries2020In: COMMUNICATIONS CHEMISTRY, ISSN 2399-3669, Vol. 3, article id 9Article in journal (Refereed)
    Abstract [en]

    The inclusion of nickel and manganese in layered sodium metal oxide cathodes for sodium ion batteries is known to improve stability, but the redox behaviour at high voltage is poorly understood. Here in situ X-ray spectroscopy studies show that the redox behaviour of oxygen anions can account for an increase in specific capacity at high voltages. Rechargeable sodium-ion batteries have recently attracted renewed interest as an alternative to Li-ion batteries for electric energy storage applications, because of the low cost and wide availability of sodium resources. Thus, the electrochemical energy storage community has been devoting increased attention to designing new cathode materials for sodium-ion batteries. Here we investigate P2- Na0.78Co1/2Mn1/3Ni1/6O2 as a cathode material for sodium ion batteries. The main focus is to understand the mechanism of the electrochemical performance of this material, especially differences observed in redox reactions at high potentials. Between 4.2 V and 4.5 V, the material delivers a reversible capacity which is studied in detail using advanced analytical techniques. In situ X-ray diffraction reveals the reversibility of the P2-type structure of the material. Combined soft X-ray absorption spectroscopy and resonant inelastic X-ray scattering demonstrates that Na deintercalation at high voltages is charge compensated by formation of localized electron holes on oxygen atoms.

    Download full text (pdf)
    FULLTEXT01
  • 13.
    Hollmark, Håkan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Soft X-Ray Physics.
    Gustafsson, Torbjörn
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Structural Chemistry.
    Edström, Kristina
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Duda, Laurent-C.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Soft X-Ray Physics.
    Resonant inelastic X-ray scattering and X-ray absorption spectroscopy on the cathode materials LiMnPO4 and LiMn0.9Fe0.1PO4: A comparative study2011In: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 13, no 45, p. 20215-20222Article in journal (Refereed)
    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.

  • 14.
    Hollmark, Håkan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Soft X-Ray Physics.
    Keech, Pete
    Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada.
    Vegelius, Johan
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Soft X-Ray Physics.
    Werme, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Soft X-Ray Physics.
    Duda, Laurent
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Soft X-Ray Physics.
    X-ray absorption spectroscopy on electrochemically oxidized Cu exposed to Na2S2011In: Corrosion Science, ISSN 0010-938X, E-ISSN 1879-0496, Vol. 54, p. 85-89Article in journal (Refereed)
    Abstract [en]

    Copper surfaces have been investigated by X-ray absorption spectroscopy after electrochemical oxidation and subsequent exposure to sulfide solution. Oxide surface layers on bulk copper surfaces were electrochemically grown in anaqueous NaOH solution at two different potentials and the resulting chemical composition was investigated using X-ray absorption spectroscopy. At both potentials the resulting surfaces consisted largely of Cu2O. At the more strongly oxidizing potential, an admixture of Cu2+-containing phases – mostly Cu(OH)2 – was detected. Sulfide exposure of both surfaces was found to completely reduce the surface from Cu2+ to Cu1+ and resulted in the formation of Cu2S with an admixture of Cu2O.

  • 15.
    House, Robert A.
    et al.
    Univ Oxford, Dept Mat, Parks Rd, Oxford OX1 3PH, England;Univ Oxford, Dept Chem, Parks Rd, Oxford OX1 3PH, England.
    Jin, Liyu
    Univ Oxford, Dept Mat, Parks Rd, Oxford OX1 3PH, England;Univ Oxford, Dept Chem, Parks Rd, Oxford OX1 3PH, England.
    Maitra, Urmimala
    Univ Oxford, Dept Mat, Parks Rd, Oxford OX1 3PH, England;Univ Oxford, Dept Chem, Parks Rd, Oxford OX1 3PH, England.
    Tsuruta, Kazuki
    Japan Synchrotron Radiat Res Inst JASRI, 1-1-1 Kouto, Sayo, Hyogo 6795198, Japan.
    Somerville, James W.
    Univ Oxford, Dept Mat, Parks Rd, Oxford OX1 3PH, England;Univ Oxford, Dept Chem, Parks Rd, Oxford OX1 3PH, England.
    Forstermann, Dominic P.
    Univ Oxford, Dept Mat, Parks Rd, Oxford OX1 3PH, England;Univ Oxford, Dept Chem, Parks Rd, Oxford OX1 3PH, England.
    Massel, Felix
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and Condensed Matter Physics.
    Duda, Laurent
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and Condensed Matter Physics.
    Roberts, Matthew R.
    Univ Oxford, Dept Mat, Parks Rd, Oxford OX1 3PH, England;Univ Oxford, Dept Chem, Parks Rd, Oxford OX1 3PH, England.
    Bruce, Peter G.
    Univ Oxford, Dept Mat, Parks Rd, Oxford OX1 3PH, England;Univ Oxford, Dept Chem, Parks Rd, Oxford OX1 3PH, England.
    Lithium manganese oxyfluoride as a new cathode material exhibiting oxygen redox2018In: Energy & Environmental Science, ISSN 1754-5692, E-ISSN 1754-5706, Vol. 11, no 4, p. 926-932Article in journal (Refereed)
    Abstract [en]

    The quantity of charge stored in transition metal oxide intercalation cathodes for Li or Na batteries is not limited by transition metal redox reactions but can also access redox reactions on O; examples include Li1.2Ni0.13Mn0.54Co0.13O2, Li2Ru0.75Sn0.25O3, Li1.2Nb0.3Mn0.4O2, Na2RuO3 and Na2/3Mg0.28Mn0.72O2. Here we show that oxyfluorides can also exhibit charge storage by O-redox. We report the discovery of lithium manganese oxyfluoride, specifically the composition, Li1.9Mn0.95O2.05F0.95, with a high capacity to store charge of 280 mA h g(-1) (corresponding to 960 W h kg(-1)) of which almost half, 130 mA h g(-1), arises from O-redox. This material has a disordered cubic rocksalt structure and the voltage-composition curve is significantly more reversible compared with ordered Li-rich layered cathodes. Unlike lithium manganese oxides such as the ordered layered rocksalt Li2MnO3, Li1.9Mn0.95O2.05F0.95 does not exhibit O loss from the lattice. The material is synthesised using a simple, one-pot mechanochemical procedure.

  • 16.
    House, Robert A.
    et al.
    Univ Oxford, Dept Mat, Parks Rd, Oxford OX1 3PH, England.
    Maitra, Urmimala
    Univ Oxford, Dept Mat, Parks Rd, Oxford OX1 3PH, England;Justus Liebig Univ Giessen, Inst Phys Chem, Heinrich Buff Ring 17,Room B48, D-35392 Giessen, Germany.
    Jin, Liyu
    Univ Oxford, Dept Mat, Parks Rd, Oxford OX1 3PH, England.
    Lozano, Juan G.
    Univ Oxford, Dept Mat, Parks Rd, Oxford OX1 3PH, England.
    Somerville, James W.
    Univ Oxford, Dept Mat, Parks Rd, Oxford OX1 3PH, England.
    Rees, Nicholas H.
    Univ Oxford, Dept Chem, Mansfield Rd, Oxford OX1 3TA, England.
    Naylor, Andrew J.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Duda, Laurent
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and Condensed Matter Physics.
    Massel, Felix
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and Condensed Matter Physics.
    Chadwick, Alan V.
    Univ Kent, Sch Phys Sci, Canterbury CT2 7NH, Kent, England.
    Ramos, Silvia
    Univ Kent, Sch Phys Sci, Canterbury CT2 7NH, Kent, England.
    Pickup, David M.
    Univ Kent, Sch Phys Sci, Canterbury CT2 7NH, Kent, England.
    McNally, Daniel E.
    Paul Scherrer Inst, Swiss Light Source, Photon Sci Div, CH-5232 Villigen, Switzerland.
    Lu, Xingye
    Paul Scherrer Inst, Swiss Light Source, Photon Sci Div, CH-5232 Villigen, Switzerland.
    Schmitt, Thorsten
    Paul Scherrer Inst, Swiss Light Source, Photon Sci Div, CH-5232 Villigen, Switzerland.
    Roberts, Matthew R.
    Univ Oxford, Dept Mat, Parks Rd, Oxford OX1 3PH, England.
    Bruce, Peter G.
    Univ Oxford, Dept Mat, Parks Rd, Oxford OX1 3PH, England;Univ Oxford, Faraday Inst, Mansfield Rd, Oxford OX1 3TA, England;Univ Oxford, Dept Chem, Mansfield Rd, Oxford OX1 3TA, England.
    What Triggers Oxygen Loss in Oxygen Redox Cathode Materials?2019In: Chemistry of Materials, ISSN 0897-4756, E-ISSN 1520-5002, Vol. 31, no 9, p. 3293-3300Article in journal (Refereed)
    Abstract [en]

    It is possible to increase the charge capacity of transition metal (TM) oxide cathodes in alkali-ion batteries by invoking redox reactions on the oxygen. However, oxygen loss often occurs. To explore what affects oxygen loss in oxygen redox materials, we have compared two analogous Na-ion cathodes, P2-Na0.67Mg0.28Mn0.72O2 and P2-Na0.78Li0.25Mn0.75O2. On charging to 4.5 V, >0.4e(-) are removed from the oxide ions of these materials, but neither compound exhibits oxygen loss. Li is retained in P2-Na0.78Li0.25Mn0.25O2 but displaced from the TM to the alkali metal layers, showing that vacancies in the TM layers, which also occur in other oxygen redox compounds that exhibit oxygen loss such as Li[Li0.2Ni0.2Mn0.6]O-2, are not a trigger for oxygen loss. On charging at 5 V, P2-Na0.78Li0.25Mn0.75O2 exhibits oxygen loss, whereas P2-Na0.67Mg0.28Mn0.72O2 does not. Under these conditions, both Na+ and Li+ are removed from P2-Na0.78Li0.25Mn0.75O2, resulting in underbonded oxygen (fewer than 3 cations coordinating oxygen) and surface-localized O loss. In contrast, for P2-Na0.67Mg0.28Mn0.72O2, oxygen remains coordinated by at least 2 Mn4+ and 1 Mg2+ ions, stabilizing the oxygen and avoiding oxygen loss.

  • 17.
    House, Robert A.
    et al.
    Univ Oxford, Dept Mat, Oxford, England.
    Maitra, Urmimala
    Univ Oxford, Dept Mat, Oxford, England.
    Perez-Osorio, Miguel A.
    Univ Oxford, Dept Mat, Oxford, England.
    Lozano, Juan G.
    Univ Oxford, Dept Mat, Oxford, England;Univ Seville, Escuela Tecn Super Ingn, Dept Ingn & Ciencia Mat & Transporte, Seville, Spain.
    Jin, Liyu
    Univ Oxford, Dept Mat, Oxford, England.
    Somerville, James W.
    Univ Oxford, Dept Mat, Oxford, England.
    Duda, Laurent
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and Condensed Matter Physics.
    Nag, Abhishek
    Diamond Light Source, Harwell, Berks, England.
    Walters, Andrew
    Diamond Light Source, Harwell, Berks, England.
    Zhou, Ke-Jin
    Diamond Light Source, Harwell, Berks, England.
    Roberts, Matthew R.
    Univ Oxford, Dept Mat, Oxford, England.
    Bruce, Peter G.
    Univ Oxford, Dept Mat, Oxford, England;Univ Oxford, Dept Chem, Oxford, England;Henry Royce Inst, Oxford, England;Faraday Inst, Didcot, Oxon, England.
    Superstructure control of first-cycle voltage hysteresis in oxygen-redox cathodes2020In: Nature, ISSN 0028-0836, E-ISSN 1476-4687, Vol. 577, no 7791, p. 502-508Article in journal (Refereed)
    Abstract [en]

    In conventional intercalation cathodes, alkali metal ions can move in and out of a layered material with the charge being compensated for by reversible reduction and oxidation of the transition metal ions. If the cathode material used in a lithium-ion or sodium-ion battery is alkali-rich, this can increase the battery's energy density by storing charge on the oxide and the transition metal ions, rather than on the transition metal alone(1-10). There is a high voltage associated with oxidation of O2- during the first charge, but this is not recovered on discharge, resulting in reduced energy density(11). Displacement of transition metal ions into the alkali metal layers has been proposed to explain the first-cycle voltage loss (hysteresis)(9,12-16). By comparing two closely related intercalation cathodes, Na-0.75[Li0.25Mn0.75]O-2 and Na-0.6[Li0.2Mn0.8]O-2, here we show that the first-cycle voltage hysteresis is determined by the superstructure in the cathode, specifically the local ordering of lithium and transition metal ions in the transition metal layers. The honeycomb superstructure of Na-0.75[Li0.25Mn0.75]O-2, present in almost all oxygen-redox compounds, is lost on charging, driven in part by formation of molecular O-2 inside the solid. The O-2 molecules are cleaved on discharge, reforming O2-, but the manganese ions have migrated within the plane, changing the coordination around O2- and lowering the voltage on discharge. The ribbon superstructure in Na-0.6[Li0.2Mn0.8]O-2 inhibits manganese disorder and hence O-2 formation, suppressing hysteresis and promoting stable electron holes on O2- that are revealed by X-ray absorption spectroscopy. The results show that voltage hysteresis can be avoided in oxygen-redox cathodes by forming materials with a ribbon superstructure in the transition metal layers that suppresses migration of the transition metal. In oxygen-redox intercalation cathodes, voltage hysteresis can be avoided by forming cathode materials with a 'ribbon' superstructure in the transition metal layers that suppresses transition metal migration.

  • 18.
    Johansson, Malin B
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Kristiansen, Paw
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and condensed matter physics.
    Baldissera, G
    Duda, Laurent C
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and condensed matter physics.
    Persson, C
    Niklasson, Gunnar A
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Österlund, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Band gap states in nanocrystalline WO3 thin films studied by soft x-ray spectroscopy, optical absorption spectroscopy and density functional calculationsManuscript (preprint) (Other academic)
  • 19. Johansson, Malin B
    et al.
    Kristiansen, Paw
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and condensed matter physics.
    Baldissera, G
    Duda, Laurent C
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and condensed matter physics.
    Persson, C
    Niklasson, Gunnar A
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Österlund, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Sub-band gap electronic states in nanocrystalline WO3 thin films studied by soft x-ray spectroscopy, optical absorption spectroscopy and density functional calculationsManuscript (preprint) (Other academic)
  • 20.
    Kim, Eun Jeong
    et al.
    Univ St Andrews, Sch Chem, St Andrews KY16 9ST, Fife, Scotland;ALISTORE ERI, F-80039 Amiens, France.
    Ma, Le Anh
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Duda, Laurent
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and Condensed Matter Physics.
    Pickup, David M.
    Univ Kent, Sch Phys Sci, Canterbury CT2 7NH, Kent, England.
    Chadwick, Alan V.
    Univ Kent, Sch Phys Sci, Canterbury CT2 7NH, Kent, England.
    Younesi, Reza
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry. ALISTORE ERI, F-80039 Amiens, France.
    Irvine, John T. S.
    Univ St Andrews, Sch Chem, St Andrews KY16 9ST, Fife, Scotland.
    Armstrong, A. Robert
    Univ St Andrews, Sch Chem, St Andrews KY16 9ST, Fife, Scotland;ALISTORE ERI, F-80039 Amiens, France.
    Oxygen Redox Activity through a Reductive Coupling Mechanism in the P3-Type Nickel-Doped Sodium Manganese Oxide2020In: ACS APPLIED ENERGY MATERIALS, ISSN 2574-0962, Vol. 3, no 1, p. 184-191Article in journal (Refereed)
    Abstract [en]

    Increasing dependence on rechargeable batteries for energy storage calls for the improvement of energy density of batteries. Toward this goal, introduction of positive electrode materials with high voltage and/or high capacity is in high demand. The use of oxygen chemistry in lithium and sodium layered oxides has been of interest to achieve high capacity. Nevertheless, a complete understanding of oxygen-based redox processes remains elusive especially in sodium ion batteries. Herein, a novel P3-type Na0.67Ni0.2Mn0.8O2, synthesized at low temperature, exhibits oxygen redox activity in high potentials. Characterization using a range of spectroscopic techniques reveals the anionic redox activity is stabilized by the reduction of Ni, because of the strong Ni 3d-O 2p hybridization states created during charge. This observation suggests that different route of oxygen redox processes occur in P3 structure materials, which can lead to the exploration of oxygen redox chemistry for further development in rechargeable batteries.

  • 21.
    Kristiansen, P. T.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and condensed matter physics. Max Planck Gesell, Fritz Haber Inst, Abt Anorgam Chem, D-14195 Berlin, Germany..
    Massel, Felix
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and condensed matter physics.
    Werme, L.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and condensed matter physics.
    Lilja, C.
    Swedish Nucl Fuel & Waste Management Co, SE-10124 Stockholm, Sweden..
    Duda, Laurent
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and condensed matter physics.
    Sulfidation of Single-Phase Oxide on Copper and as Powder Studied Using Soft X-Ray Spectroscopy2015In: Journal of the Electrochemical Society, ISSN 0013-4651, E-ISSN 1945-7111, Vol. 162, no 14, p. C785-C791Article in journal (Refereed)
    Abstract [en]

    The high corrosion resistance of copper is a key feature in the design of copper-lined canisters that will be utilized to protect people and the environment from dangers of spent nuclear fuel far into the future. Our present study sheds light on the effects that sulfide ions in otherwise relatively benign anoxic groundwater may have on the copper of the container material. Using soft X-ray spectroscopy, we have studied the chemistry of the transformation of single-phase copper oxide cover layers (cuprite, tenorite, paratacamite) as well as single-phase oxide powders (paratacamite and malachite) when exposed to aqueous sulfide solutions. While X-ray diffraction shows that the main bulk of the oxides are nearly unaffected, Cu L-edge absorption spectroscopy shows that a cover layer of about 100 nm thickness on the metal substrate is transformed from Cu(II)- to Cu(I)-species. By contrast, paratacamite and malachite powders exposed to the same kind of aqueous sulfide solutions show much less transformation to Cu(I)-species. We conclude that the main mechanism for reduction of Cu(II) on copper is the comproportionation reaction between divalent copper ions from the covering oxide and the underlying metallic copper atoms to form monovalent copper ions. By contrast, the absence of metallic copper inhibits this mechanism in the powders.

    Download full text (pdf)
    fulltext
  • 22.
    Kristiansen, Paw
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and condensed matter physics.
    Massel, F
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and condensed matter physics.
    Werme, L
    Lilja, C
    Duda, Laurent C
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and condensed matter physics.
    X-ray spectroscopic studies of selected Cu(II) compounds exposed to dilute sulfide solutionsManuscript (preprint) (Other academic)
  • 23.
    Kristiansen, Paw
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and condensed matter physics.
    Rocha, T C R
    Knop-Gericke, A
    Guo, J H
    Duda, LaurentC
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and condensed matter physics.
    Reaction cell for in situ soft x-ray absorption spectroscopy and resonant inelastic x-ray scattering measurements of heterogeneous catalysis up to 1 atm and 250 °C2013In: Review of Scientific Instruments, ISSN 0034-6748, E-ISSN 1089-7623, Vol. 84, no 11, p. 113107-Article in journal (Refereed)
    Abstract [en]

    We present a novel in situ reaction cell for heterogeneous catalysis monitored in situ by x-ray absorption spectroscopy (XAS) and resonant inelastic x-ray scattering (RIXS). The reaction can be carried out at a total pressure up to 1 atm, a regime that has not been accessible to comparable in situ techniques and thus closes the pressure gap to many industrial standard conditions. Two alternate catalyst geometries were tested: A) a thin film evaporated directly onto a x-ray transparent membrane with a flowing reaction gas mixture behind it or B) a powder placed behind both the membrane and a gap of flowing reaction gas mixture. To illustrate the working principle and feasibility of our reaction cell setup we have chosen ethylene epoxidation over a silver catalyst as a test case. The evolution of incorporated oxygen species was monitored by total electron/fluorescence yield O K-XAS as well as O K-RIXS, which is a powerful method to separate contributions from inequivalent sites. We find that our method can reliably detect transient species that exist during catalytic reaction conditions that are hardly accessible using other spectroscopic methods.

    Download full text (pdf)
    fulltext
  • 24.
    Kristiansen, Paw
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and condensed matter physics.
    Rocha, T C R
    Knop-Gericke, A
    Schlögl, R
    Duda, Laurent C
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and condensed matter physics.
    In situ soft x-ray spectroscopy of ethylene epoxidation over Ag at 1 atm and 230°CManuscript (preprint) (Other academic)
    Abstract [en]

    We perform in situ soft x-ray XAS and RIXS of ethylene epoxidation over Ag. We find that several oxygen species are loaded into the Ag when it is heated to 230C and exposed to oxygen containing mixtures. Candidate fingerprints of the intensively debated electrophilic oxygen species, Oelec, that is necessary for the epoxidation process, are reached in this work.

  • 25.
    Luo, Kun
    et al.
    Univ Oxford, Dept Mat & Chem, Parks Rd, Oxford OX1 3PH, England..
    Roberts, Matthew R.
    Univ Oxford, Dept Mat & Chem, Parks Rd, Oxford OX1 3PH, England..
    Hao, Rong
    Univ Oxford, Dept Mat & Chem, Parks Rd, Oxford OX1 3PH, England..
    Guerrini, Niccolo
    Univ Oxford, Dept Mat & Chem, Parks Rd, Oxford OX1 3PH, England..
    Pickup, David M.
    Univ Kent, Sch Phys Sci, Canterbury CT2 7NH, Kent, England..
    Liu, Yi-Sheng
    Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Adv Light Source, Berkeley, CA 94720 USA..
    Edström, Kristina
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Guo, Jinghua
    Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Adv Light Source, Berkeley, CA 94720 USA..
    Chadwick, Alan V.
    Univ Kent, Sch Phys Sci, Canterbury CT2 7NH, Kent, England..
    Duda, Laurent C.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and Condensed Matter Physics.
    Bruce, Peter G.
    Univ Oxford, Dept Mat & Chem, Parks Rd, Oxford OX1 3PH, England..
    Charge-compensation in 3d-transition-metal-oxide intercalation cathodes through the generation of localized electron holes on oxygen2016In: Nature Chemistry, ISSN 1755-4330, E-ISSN 1755-4349, Vol. 8, no 7, p. 684-691Article in journal (Refereed)
    Abstract [en]

    During the charging and discharging of lithium-ion-battery cathodes through the de-and reintercalation of lithium ions, electroneutrality is maintained by transition-metal redox chemistry, which limits the charge that can be stored. However, for some transition-metal oxides this limit can be broken and oxygen loss and/or oxygen redox reactions have been proposed to explain the phenomenon. We present operando mass spectrometry of O-18-labelled Li-1.2[Ni0.132+Co0.133+Mn0.544+]O-2, which demonstrates that oxygen is extracted from the lattice on charging a Li-1.2[Ni0.132+Co0.133+Mn0.544+]O-2 cathode, although we detected no O-2 evolution. Combined soft X-ray absorption spectroscopy, resonant inelastic X-ray scattering spectroscopy, X-ray absorption near edge structure spectroscopy and Raman spectroscopy demonstrates that, in addition to oxygen loss, Li+ removal is charge compensated by the formation of localized electron holes on O atoms coordinated by Mn4+ and Li+ ions, which serve to promote the localization, and not the formation, of true O-2(2-)( peroxide, O-O similar to 1.45 angstrom) species. The quantity of charge compensated by oxygen removal and by the formation of electron holes on the O atoms is estimated, and for the case described here the latter dominates.

  • 26.
    Ma, Le Anh
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Massel, Felix
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and Condensed Matter Physics.
    Naylor, Andrew J.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Duda, Laurent
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and Condensed Matter Physics.
    Younesi, Reza
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Understanding charge compensation mechanisms in Na0.56Mg0.04Ni0.19Mn0.70O22019In: Communications chemistry, E-ISSN 2399-3669, Vol. 2, article id 125Article in journal (Refereed)
    Abstract [en]

    Sodium-ion batteries have become a potential alternative to Li-ion batteries due to the abundance of sodium resources. Sodium-ion cathode materials have been widely studied with particular focus on layered oxide lithium analogues. Generally, the capacity is limited by the redox processes of transition metals. Recently, however, the redox participation of oxygen gained a lot of research interest. Here the Mg-doped cathode material P2-Na0.56Mg0.04Ni0.19Mn0.70O2 is studied, which is shown to exhibit a good capacity (ca. 120 mAh/g) and high average operating voltage (ca. 3.5 V vs. Na+/Na). Due to the Mg-doping, the material exhibits a reversible phase transition above 4.3 V, which is attractive in terms of lifetime stability. In this study, we combine X-ray photoelectron spectroscopy, X-ray absorption spectroscopy and resonant inelastic X-ray scattering spectroscopy techniques to shed light on both, cationic and anionic contributions towards charge compensation.

    Download full text (pdf)
    fulltext
  • 27. Maganas, Dimitrios
    et al.
    Kristiansen, Paw
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and condensed matter physics.
    Duda, Laurent-Claudius
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and condensed matter physics.
    Gericke, Axel Knop
    DeBeer, Serena
    Schlögl, Robert
    Neese, Frank
    Combined Experimental and ab initio Multi Reference Configuration Interaction study of the Resonant Inelastic X-RayScattering spectrum of CO22014In: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 118, no 35, p. 20163-20175Article in journal (Refereed)
    Abstract [en]

    The fundamental problem of the symmetry breaking in the resonant inelastic X-ray scattering (RIXS) of the CO2 gas molecule is studied. The measurements were performed under catalytically relevant conditions within an in-house constructed reaction cell. The experimental RIXS plane is constructed from a sequence of resonances, covering the near-edge X-ray absorption fine structure (NEXAFS) spectrum up to 539 eV. The spectra show significant sensitivity with respect to the excitation frequency. The NEXAFS absorption spectrum, as well as the corresponding RIXS spectra, is interpreted with the aid of multireference configuration interaction (MRCI) theory. In this framework, the configuration interaction space spans the space of the intermediate and final states with single and single-double excitations. The dynamic character of the RIXS spectra is investigated by considering the electronic-nuclear vibrational coupling with the bending and antisymmetric stretching vibrations in the important intermediate excited states. In addition, the vibronic coupling mechanism involving the Renner-Teller effect and the core-hole localization pseudo-Jahn-Teller effect of the intermediate states is fully considered. The physical origin of the observed spectral features is discussed qualitatively and quantitatively in terms of individual core-to-valence excitations and valence-to-core decays, respectively. The computational protocol presented here, based on multireference wave function ab initio theory, serves as an important reference for future theoretical and experimental applications of RIXS spectroscopy.

  • 28.
    Magnuson, Martin
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics.
    Duda, Laurent
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics.
    Butorin, Sergei
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics.
    Kuiper, Pieter
    Nordgren, Joseph
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics.
    Large magnetic circular dichroism in rensonant inelastic x-ray scattering at the Mn L-edge of Mn-Zn ferrite2006In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 74, no 17, p. 172409-Article in journal (Refereed)
    Abstract [en]

    We report resonant inelastic x-ray scattering (RIXS) excited by circularly polarized x rays on Mn-Zn ferrite at the Mn L2,3 resonances. We demonstrate that crystal-field excitations, as expected for localized systems, dominate the RIXS spectra and thus their dichroic asymmetry cannot be interpreted in terms of spin-resolved partial density of states, which has been the standard approach for RIXS dichroism. We observe large dichroic RIXS at the L2 resonance which we attribute to the absence of metallic core hole screening in the insulating Mn ferrite. On the other hand, reduced L3 -RIXS dichroism is interpreted as an effect of longer scattering time that enables spin-lattice core hole relaxation via magnons and phonons occurring on a femtosecond time scale.

    Download full text (pdf)
    fulltext
  • 29.
    Magnuson, Martin
    et al.
    Linkoping Univ, IFM, Dept Phys Chem & Biol, Thin Film Phys Div, SE-58183 Linkoping, Sweden..
    Schmitt, Thorsten
    SLS, Paul Scherrer Inst, Res Dept Synchrotron Radiat & Nanotechnol, CH-5232 Villigen, Switzerland..
    Duda, Laurent-C.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and Condensed Matter Physics.
    Polarization-dependent resonant inelastic X-ray scattering study at the Cu L and O K-edges of YBa2Cu3O7-x2018In: Journal of Electron Spectroscopy and Related Phenomena, ISSN 0368-2048, E-ISSN 1873-2526, Vol. 224, p. 38-44Article in journal (Refereed)
    Abstract [en]

    We present a study on the high-Tc superconductor (HTSC) YBa2Cu3O7-x (YBCO) using polarization dependent X-ray absorption and resonant inelastic X-ray scattering. High-resolution measurements using synchrotron-radiation are compared with calculations using a quasi-atomic multiplet approach performed at the Cu 2p(3/2)-edge of YBCO. We use a multiplet approach within the single impurity Anderson model to reproduce and understand the character of the localized low-energy excitations in YBCO. We observe a distinct peak at about 0.5 eV in OK RIXS. This peak shows dependence on doping, incident energy, and momentum transfer that suggests that it has a different origin than the previously discussed cuprate bimagnons. Therefore, we assign it to bimagnon excitations within the Zhang Rice bands and/or the Upper Hubbard bands, respectively. (C) 2017 Elsevier B.V. All rights reserved.

    Download full text (pdf)
    fulltext
  • 30. Magnuson, Martin
    et al.
    Schmitt, Thorsten
    Strocov, Vladimir N.
    Schlappa, Justina
    Kalabukhov, Alexej S.
    Duda, Laurent-Claudius
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and condensed matter physics.
    Self-doping processes between planes and chains in the metal-to-superconductor transition of YBa2Cu3O6.92014In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 4, p. 7017-Article in journal (Refereed)
    Abstract [en]

    The interplay between the quasi 1-dimensional CuO-chains and the 2-dimensional CuO2 planes of YBa2Cu3O61x (YBCO) has been in focus for a long time. Although the CuO-chains are known to be important as charge reservoirs that enable superconductivity for a range of oxygen doping levels in YBCO, the understanding of the dynamics of its temperature-driven metal-superconductor transition (MST) remains a challenge. We present a combined study using x-ray absorption spectroscopy and resonant inelastic x-ray scattering (RIXS) revealing how a reconstruction of the apical O(4)-derived interplanar orbitals during the MST of optimally doped YBCO leads to substantial hole-transfer from the chains into the planes, i.e. self-doping. Our ionic model calculations show that localized divalent charge-transfer configurations are expected to be abundant in the chains of YBCO. While these indeed appear in the RIXS spectra from YBCO in the normal, metallic, state, they are largely suppressed in the superconducting state and, instead, signatures of Cu trivalent charge-transfer configurations in the planes become enhanced. In the quest for understanding the fundamental mechanism for high-Tc-superconductivity (HTSC) in perovskite cuprate materials, the observation of such an interplanar self-doping process in YBCO opens a unique novel channel for studying the dynamics of HTSC.

    Download full text (pdf)
    fulltext
  • 31. Maitra, Urmimala
    et al.
    House, Robert
    Somerville, James
    Tapia-Ruiz, Nuria
    Lozano, Juan
    Guerrini, Niccoló
    Hao, Rong
    Luo, Kun
    Jin, Liyu
    Pérez-Osorio, Miguel
    Massel, Felix
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and Condensed Matter Physics.
    Pickup, David
    Ramos, Silvia
    Lu, Xingye
    McNally, Daniel
    Chadwick, Alan
    Giustino, Feliciano
    Schmitt, Thorsten
    Duda, Laurent
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and Condensed Matter Physics.
    Roberts, Matthew
    Bruce, Peter
    Oxygen redox chemistry without excess alkali-metal ions in Na2/3[Mg0.28Mn0.72]O22018In: Nature Chemistry, ISSN 1755-4330, E-ISSN 1755-4349, Vol. 10, p. 288-295Article in journal (Refereed)
    Abstract [en]

    The search for improved energy-storage materials has revealed Li-and Na-rich intercalation compounds as promising high-capacity cathodes. They exhibit capacities in excess of what would be expected from alkali-ion removal/reinsertion and charge compensation by transition-metal (TM) ions. The additional capacity is provided through charge compensation by oxygen redox chemistry and some oxygen loss. It has been reported previously that oxygen redox occurs in O 2p orbitals that interact with alkali ions in the TM and alkali-ion layers (that is, oxygen redox occurs in compounds containing Li+-O(2p)-Li+ interactions). Na2/3[Mg0.28Mn0.72]O2 exhibits an excess capacity and here we show that this is caused by oxygen redox, even though Mg2+ resides in the TM layers rather than alkali-metal (AM) ions, which demonstrates that excess AM ions are not required to activate oxygen redox. We also show that, unlike the alkali-rich compounds, Na2/3[Mg0.28Mn0.72]O2 does not lose oxygen. The extraction of alkali ions from the alkali and TM layers in the alkalirich compounds results in severely underbonded oxygen, which promotes oxygen loss, whereas Mg2+ remains in Na2/3[Mg0.28Mn0.72]O2, which stabilizes oxygen.

  • 32.
    Massel, Felix
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and Condensed Matter Physics.
    Ahmadi, Sareh
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and Condensed Matter Physics.
    Hahlin, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and Condensed Matter Physics.
    Liu, Y.-S
    Advanced Light Source, Lawrence Berkeley Laboratory, Berkeley, CA, USA.
    Guo, J.-H.
    Advanced Light Source, Lawrence Berkeley Laboratory, Berkeley, CA, USA.
    Edvinsson, Tomas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Rensmo, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and Condensed Matter Physics.
    Duda, Laurent
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and Condensed Matter Physics.
    Transition metal doping effects in Co-phosphate catalysts for water splitting studied with XAS2018In: Journal of Electron Spectroscopy and Related Phenomena, ISSN 0368-2048, E-ISSN 1873-2526, p. 3-7Article in journal (Refereed)
    Abstract [en]

    Metal oxides as oxygen evolution reaction (OER) catalysts for water splitting are ubiquitous in research and application. Pure and doped (or hybrid) Co oxide systems are of particular interest due to their good efficiency. However, the electronic effects of different dopants are still unclear in many of these systems. We present a study of doped Co-phosphate (P-i) films deposited electrochemically from aqueous solutions of neutral pH using an X-ray absorption spectroscopy (XAS), a technique that can reveal important information about catalytically active states. These hybrid films, obtained from solutions containing both Co ions and another transition metal (TM) ion (TM = Mn, Fe, Ni), were analyzed with XAS at the TM L-edges and the O K-edge. We find that a large concentration of Co3+-ions in the films and a low-lying edge of the O 2p conduction band (CB) are good indicators for the OER efficiency of the films. Our results show that native Co-P-i is close to optimal for the OER activity at low deposition potential. However, Mn- and Ni-doped systems have promising properties when deposited at higher potentials because these ions tend to stabilize the Co3+-state in the films as well as the position of the O 2p-edge CB (a few tenths of 1 eV), in contrast to native Co-Pi films.

  • 33.
    Massel, Felix
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and Condensed Matter Physics.
    Hikima, Kazuhiro
    Rensmo, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and Condensed Matter Physics.
    Suzuki, Kota
    Hirayama, Masaaki
    Xu, Chao
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry. Univ Cambridge, Dept Chem, Lensfield Rd, Cambridge CB2 1EW, England.
    Younesi, Reza
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Liu, Yi-Sheng
    Guo, Jinghua
    Kanno, Ryoji
    Hahlin, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and Condensed Matter Physics.
    Duda, Laurent
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and Condensed Matter Physics.
    Excess lithium in transition metal layers of epitaxially grown thin film cathodes of Li2MnO3 leads to rapid loss of covalency during first battery cycle2019In: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 123, no 47, p. 28519-28526Article in journal (Refereed)
    Abstract [en]

    We have investigated the initial-cycle battery behavior of epitaxial thin films of Li2MnO3-cathodes by employing resonant inelastic X-ray scattering (RIXS) at the O K- and Mn L3-edges. Thin films (25 nm thickness) with Li/Mn-ratios of 2.06 (stoichiometric) and 2.27 (over-stoichiometric), respectively, were epitaxially grown by pulsed laser deposition and electrochemically cycled as battery cathodes in half-cell setup, stopped at potentials for full charge (delithiation) and complete discharge (relithiation), respectively, for X-ray analysis. Using RIXS, we find that significant anionic reactions take place in both materials upon initial delithiation. However, no signatures of localized oxygen holes are found in O K-RIXS of the Li2MnO3 regardless of Li/Mn-ratio. Instead, the top of the oxygen valence band is depleted of electrons forming delocalized empty states upon delithiation. Mn L-RIXS of the over-stoichiometric cathode material shows a progressive loss of charge transfer state intensity during the first battery cycle, revealing a more rapid loss of Mn--O covalency in the over-stoichiometric material.

  • 34.
    Nordgren, Joseph
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II.
    Butorin, Sergei
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II.
    Duda, Laurent
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II.
    Guo, Jinghua
    Rubensson, Jan-Erik
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II.
    Soft x-ray fluorescence spectroscopy for materials science and chemical physics2002In: Chemical Applications of Synchrotron Radiation: Part I: Dynamics and VUV Spectroscopy, World Scientific Publishing Co. Pte. Ltd. , 2002, p. 518-572Chapter in book (Refereed)
  • 35.
    Nordgren, Joseph
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II.
    Butorin, Sergei
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II.
    Guo, Jinghua
    Duda, Laurent
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II.
    Soft x-ray emission and resonant inelastic x-ray scattering spectroscopy2006In: Handbook of Applied Solid State Spectroscopy, Springer Science+Business Media, LLC , 2006, p. 595-659Chapter in book (Refereed)
  • 36.
    Nordlinder, Sara
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Structural Chemistry. Physics, Department of Physics and Materials Science, Physics II. strukturkemi.
    Augustsson, A
    Department of Physics. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Structural Chemistry. Physics, Department of Physics and Materials Science, Physics II.
    Schmitt, T
    Department of Physics. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Structural Chemistry. Physics, Department of Physics and Materials Science, Physics II.
    Guo, J
    Duda, L
    Department of Physics. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Structural Chemistry. Physics, Department of Physics and Materials Science, Physics II.
    Nordgren, J
    Department of Physics. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Structural Chemistry. Physics, Department of Physics and Materials Science, Physics II.
    Gustafsson, Torbjörn
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Structural Chemistry. Physics, Department of Physics and Materials Science, Physics II. strukturkemi.
    Edström, Kristina
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Materials Chemistry, Structural Chemistry. Physics, Department of Physics and Materials Science, Physics II. strukturkemi.
    Redox behavior of vanadium oxide nanotubes as studied by X-ray photoelectron spectroscopy and soft X-ray absorption spectroscopy.2003In: Chemistry of Materials, Vol. 15, no 16, p. 3227-3232Article in journal (Refereed)
  • 37. Schmitt, T
    et al.
    Duda, L
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics and Materials Science, Physics II.
    Augustsson, A
    Guo, J H
    Nordgren, J
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics and Materials Science, Physics II.
    Downes, J E
    McGuinness, C
    Smith, K E
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics and Materials Science, Physics II.
    Dhalenne, G
    Revcoloevshci, A
    Klemm, M
    Horn, S
    Resonant soft X-ray emission spectroscopy of V2O3, VO2 and NaV2O52002In: Surface Review and Letters, Vol. 9, no 2, p. 1369-1374Article in journal (Refereed)
  • 38.
    Schmitt, Thorsten
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II. Chemistry, Department of Materials Chemistry, Structural Chemistry.
    Augustsson, Andreas
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II. Chemistry, Department of Materials Chemistry, Structural Chemistry.
    Duda, Laurent
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II. Chemistry, Department of Materials Chemistry, Structural Chemistry.
    Nordgren, Joseph
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II. Chemistry, Department of Materials Chemistry, Structural Chemistry.
    Höwing, Jonas
    Department of Physics and Materials Science, Physics II. Chemistry, Department of Materials Chemistry, Structural Chemistry. strukturkemi.
    Gustafsson, Torbjörn
    Department of Physics and Materials Science, Physics II. Chemistry, Department of Materials Chemistry, Structural Chemistry. strukturkemi.
    Li insertion into V6O13 battery cathodes studies by soft x-ray spectroscopies2004In: Journal of Applied Physics, Vol. 95, no 11, p. 6444-6449Article in journal (Refereed)
    Abstract [en]

    Changes in the electronic structure of V6O13 on lithium-ion insertion into battery cathod were studied by soft x-ray absorption (SXA) spectroscopy and resonant soft x-ray emission (SXE) spectroscopy. SXA and resonant SXE spectra were recorded ex situ for cycled battery cathodes discharged to different potentials corresponding closely to distinct lithiated stages (LixV6O13,x=0,1,...,6).Large systematic change were observed in the vanadium and oxygen x-ray spectra, reflecting the effects of electrochemical reduction associated with the Li-ion insertion. Spectral shape analysis indicates that a large fraction of the vanadium ions have been reduced to V3+ ions for the highest degree of, x=6. Neverrtheless, further lithiation may be possible, in view of the linear development of the vanadium and oxygen bands on charge uptake.

  • 39.
    Schmitt, Thorsten
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II. Chemistry, Department of Materials Chemistry, Structural Chemistry.
    Augustsson, Andreas
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II. Chemistry, Department of Materials Chemistry, Structural Chemistry.
    Nordgren, Joseph
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II. Chemistry, Department of Materials Chemistry, Structural Chemistry.
    Duda, Laurent
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II. Chemistry, Department of Materials Chemistry, Structural Chemistry.
    Höwing, Jonas
    Department of Physics and Materials Science, Physics II. Chemistry, Department of Materials Chemistry, Structural Chemistry. strukturkemi.
    Gustafsson, Torbjörn
    Department of Physics and Materials Science, Physics II. Chemistry, Department of Materials Chemistry, Structural Chemistry. strukturkemi.
    Schwingenschlögl, U
    Eyert, V
    Electronic structure of Li-inserted V6O13 battery cathodes: Rigid band behavior and effects of hybridization2005In: Applied Physics Letters, Vol. 86, no 6, p. 064101-Article in journal (Refereed)
    Abstract [en]

    Resonant soft x-ray emission (SXE) spectroscopy was used to study the electronic structure of LixV6O13 battery cathodes. We observe that the V 3d-bands of V6O13 exhibit a rather rigid behavior. Upon lithiation, electrons enter the top of the valence band and add intensity to the corresponding part of the V L-emission spectrum without significantly distorting the lower lying bands. We perform ab initio calculations which are in good agreement with the experimental results. Moreover, we find that lithiation leads to an overall decrease of the V 3d–O 2p hybridization. In contrast to x-ray diffraction, it is possible to study charge transfer effects in Li-batteries with SXE spectroscopy over the entire lithiation range.

  • 40.
    Schmitt, Thorsten
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II.
    Duda, Laurent
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II.
    Matsubara, M
    Augustsson, Andreas
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II.
    Trif, Florentina
    Guo, Jinghua
    Gridneva, L
    Department of Physics and Materials Science, Physics II.
    Uozumi, T
    Kotani, A
    Nordgren, Joseph
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II.
    Resonant soft X-ray emission spectroscopy of doped and undoped vanadium oxides2004In: Journal of Alloys and Compounds, Vol. 362, no 1-2, p. 143-150Article in journal (Refereed)
  • 41.
    Schmitt, Thorsten
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II. Physics IV.
    Duda, Laurent
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II. Physics IV.
    Matsubara, M
    Mattesini, M
    Klemm, M
    Augustsson, Andreas
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II. Physics IV.
    Guo, Jinghua
    Uozumi, T
    Horn, S
    Ahuja, Rajeev
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II. Physics IV.
    Kotani, A
    Nordgren, Joseph
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II. Physics IV.
    Electronic structure studies of V6O13 by soft x-ray emission spectroscopy: Band-like and excitonic vanadium states2004In: Physical Review B, Vol. 69, no 12Article in journal (Refereed)
  • 42.
    Schmitt, Thorsten
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics, Physics II.
    Duda, Laurent-C.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics.
    Matsubara, Masahiko
    Augustsson, Andreas
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics.
    Trif, Florentina
    Guo, Jinghua
    Gridneva, Lidia
    Uozumi, Takayuki
    Kotani, Akio
    Nordgren, Joseph
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics, Physics II.
    Resonant soft X-ray emission spectroscopy of doped and undoped vanadium oxides2004In: Journal of Alloys and Compounds, ISSN 0925-8388, E-ISSN 1873-4669, Vol. 362, no 1-2, p. 143-150Article in journal (Refereed)
    Abstract [en]

    ResonantsoftX-rayemission (RSXE) spectra of NaV2O5, MoxV1−xO2 and V2O3 have been recorded for a series of excitation energies at resonances of the V L- and O K-absorption band. Resonant excitation allows us, firstly, to separate V 3d and O 2p projected density-of-states of the valence band and, secondly, to study charge-neutral low-energy excitations due to resonant inelastic X-ray scattering (RIXS). We found that both the V L- and the O K-emission spectra clearly show components originating from O 2p- and V 3d-states, reflecting the high degree of hybridization of the valence band in all compounds. At threshold excitation we observed that NaV2O5 spectra are dominated by RIXS whereas MoxV1−xO2 and V2O3spectra show bandlike features, which may be due to differences in the correlation effects of the compounds. We compared the RSXE spectra with cluster model calculations, which gives a good account for NaV2O5whereas the RSXE spectra of the other compounds show RIXS only at certain energies well above the threshold. In fact, we interpret the trend in the RSXE spectra of the MoxV1−xO2 compound system as a successive filling of the (rigid) V 3d band with increasing Mo content.

  • 43. Strambeanu, N
    et al.
    Rus, V
    Duda, L
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics and Materials Science, Physics II.
    Cocheci, D
    Brinzei, E
    The thermodynamic study of the silica elimination from the high purity water through some ion-exchange deeply overlaid systems2002In: Revista De Chimie, Vol. 53, no 6, p. 460-463Article in journal (Refereed)
  • 44.
    Söderström, Johan
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics.
    Gråsjö, Johan
    Medicinska vetenskapsområdet, Faculty of Pharmacy, Department of Pharmacy.
    Kashtanov, S
    Bergström, Christel
    Medicinska vetenskapsområdet, Faculty of Pharmacy, Department of Pharmacy.
    Agåker, Marcus
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics.
    Schmitt, Thorsten
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics.
    Augustsson, Andreas
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics.
    Duda, Laurent
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics.
    Guo, Jinghua
    Nordgren, Joseph
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics.
    Luo, Yi
    Artursson, Per
    Medicinska vetenskapsområdet, Faculty of Pharmacy, Department of Pharmacy.
    Rubensson, Jan-Erik
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics.
    X-ray yield and selectively excited X-ray emission spectra of atenolol and nadolol.2005In: J Electr Spectr, Vol. 144-147, p. 283-285Article in journal (Refereed)
  • 45. Yablonskikh, M V
    et al.
    Yarmoshenko, Y M
    Solovyev, I V
    Kurmaev, E Z
    Duda, Laurent
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II.
    Schmitt, Thorsten
    Magnuson, Martin
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II.
    Nordgren, Joseph
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Physics. Department of Physics and Materials Science, Physics II.
    Moewes, A
    Resonant L-alpha,L-beta X-ray emission and L-3,L-2 X-ray absorption spectra of 3d metals in Co(2)MnZ (Z = Al, Ga, Sn, Sb) Heusler alloys as an element- selective probe of spin character of valence band2005In: Journal of Electron Spectroscopy and Related Phenomena, Vol. 144, p. 765-769Article in journal (Refereed)
1 - 45 of 45
CiteExportLink to result list
Permanent 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