title: Structure of Nano-sized CeO2Materials: Combined Scattering and Spectroscopic Investigations.
abstract: The structure of several nano-sized ceria, CeO2, systems was investigated using neutron and X-ray diffraction and X-ray absorption spectroscopy. Whilst both diffraction and total pair distribution functions (PDFs) revealed that in all of the samples the occupancy of both Ce4+and O2-are very close to the ideal stoichiometry, the analysis using Reverse Monte Carlo technique revealed significant disorder around oxygen atoms in the nano-sized ceria samples in comparison to the highly crystalline NIST standard. In addition, the analysis revealed that the main differences observed in the pair correlations from various X-ray and neutron diffraction techniques were attributable to the particle size of the CeO2prepared by the reported three methods. Furthermore, detailed analysis of the Ce L3- and K-edge EXAFS data support this finding; in particular the decrease in higher shell coordination numbers with respect to the NIST standard, is attributed to differences in particle size.
authors: Department of Chemistry, University College London, 20 Gordon Street, London, WC1H 0AJ, UK.
authors: Huw R
authors: HR
authors: Marchbank
authors: Department of Chemistry, University College London, 20 Gordon Street, London, WC1H 0AJ, UK.
authors: Adam H
authors: AH
authors: Clark
authors: Johnson Matthey Technology Centre, Blount's Court, Sonning Common, Reading, RG4 9NH, UK.
authors: Timothy I
authors: TI
authors: Hyde
authors: ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon, OX11 0QX, UK.
authors: Helen Y
authors: HY
authors: Playford
authors: ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon, OX11 0QX, UK.|Diamond Light Source, Harwell Science and Innovation campus, Didcot, Oxon, OX11 0DE, UK.|Spallation Neutron Source, One Bethel Valley Road, MS-6475, Oak Ridge, TN, 37831-6475, USA.
authors: Matthew G
authors: MG
authors: Tucker
authors: Johnson Matthey Technology Centre, Blount's Court, Sonning Common, Reading, RG4 9NH, UK.
authors: David
authors: D
authors: Thompsett
authors: Johnson Matthey Technology Centre, Blount's Court, Sonning Common, Reading, RG4 9NH, UK.
authors: Janet M
authors: JM
authors: Fisher
authors: X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, USA.
authors: Karena W
authors: KW
authors: Chapman
authors: X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, USA.
authors: Kevin A
authors: KA
authors: Beyer
authors: ESRF-The European Synchrotron, CS40220, 38043, Grenoble, Cedex 9, France.
authors: Manuel
authors: M
authors: Monte
authors: Netherlands Organization for Scientific Research (NWO), ESRF-The European Synchrotron, CS40220, 38043, Grenoble, Cedex 9, France.|CNR-ISMN, Consiglio Nazionale delle Ricerche, Istituto per lo Studio dei Materiali Nanostrutturati, Via, Ugo La Malfa 153, 90146, Palermo, Italy.
authors: Alessandro
authors: A
authors: Longo
authors: Department of Chemistry, University College London, 20 Gordon Street, London, WC1H 0AJ, UK.
authors: Gopinathan
authors: G
authors: Sankar
keywords: EXAFS; Reverse Monte Carlo; Rietveld analysis; ceria; pair distribution functions