The Surface Reactions of Ethanol over UO2(100) Thin Film

Handle URI:
http://hdl.handle.net/10754/598731
Title:
The Surface Reactions of Ethanol over UO2(100) Thin Film
Authors:
Senanayake, Sanjaya D.; Mudiyanselage, Kumudu; Burrell, Anthony K; Sadowski, Jerzy T.; Idriss, Hicham
Abstract:
The study of the reactions of oxygenates on well-defined oxide surfaces is important for the fundamental understanding of heterogeneous chemical pathways that are influenced by atomic geometry, electronic structure and chemical composition. In this work, an ordered uranium oxide thin film surface terminated in the (100) orientation is prepared on a LaAlO3 substrate and studied for its reactivity with a C-2 oxygenate, ethanol (CH3CH2OH). With the use of synchrotron X-ray photoelectron spectroscopy (XPS), we have probed the adsorption and desorption processes observed in the valence band, C1s, O1s and U4f to investigate the bonding mode, surface composition, electronic structure and probable chemical changes to the stoichiometric-UO2(100) [smooth-UO2(100)] and Ar+-sputtered UO2(100) [rough-UO2(100)] surfaces. Unlike UO2(111) single crystal and UO2 thin film, Ar-ion sputtering of this UO2(100) did not result in noticeable reduction of U cations. The ethanol molecule has C-C, C-H, C-O and O-H bonds, and readily donates the hydroxyl H while interacting strongly with the UO2 surfaces. Upon ethanol adsorption (saturation occurred at 0.5 ML), only ethoxy (CH3CH2O-) species is formed on smooth-UO2(100) whereas initially formed ethoxy species are partially oxidized to surface acetate (CH3COO-) on the Ar+-sputtered UO2(100) surface. All ethoxy and acetate species are removed from the surface between 600 and 700 K.
KAUST Department:
SABIC - Corporate Research and Innovation Center (CRI) at KAUST
Citation:
The Surface Reactions of Ethanol over UO2(100) Thin Film 2015:151008144757007 The Journal of Physical Chemistry C
Publisher:
American Chemical Society (ACS)
Journal:
The Journal of Physical Chemistry C
Issue Date:
8-Oct-2015
DOI:
10.1021/acs.jpcc.5b08577
Type:
Article
ISSN:
1932-7447; 1932-7455
Additional Links:
http://pubsdc3.acs.org/doi/10.1021/acs.jpcc.5b08577
Appears in Collections:
Articles

Full metadata record

DC FieldValue Language
dc.contributor.authorSenanayake, Sanjaya D.en
dc.contributor.authorMudiyanselage, Kumuduen
dc.contributor.authorBurrell, Anthony Ken
dc.contributor.authorSadowski, Jerzy T.en
dc.contributor.authorIdriss, Hichamen
dc.date.accessioned2016-02-25T14:17:37Zen
dc.date.available2016-02-25T14:17:37Zen
dc.date.issued2015-10-08en
dc.identifier.citationThe Surface Reactions of Ethanol over UO2(100) Thin Film 2015:151008144757007 The Journal of Physical Chemistry Cen
dc.identifier.issn1932-7447en
dc.identifier.issn1932-7455en
dc.identifier.doi10.1021/acs.jpcc.5b08577en
dc.identifier.urihttp://hdl.handle.net/10754/598731en
dc.description.abstractThe study of the reactions of oxygenates on well-defined oxide surfaces is important for the fundamental understanding of heterogeneous chemical pathways that are influenced by atomic geometry, electronic structure and chemical composition. In this work, an ordered uranium oxide thin film surface terminated in the (100) orientation is prepared on a LaAlO3 substrate and studied for its reactivity with a C-2 oxygenate, ethanol (CH3CH2OH). With the use of synchrotron X-ray photoelectron spectroscopy (XPS), we have probed the adsorption and desorption processes observed in the valence band, C1s, O1s and U4f to investigate the bonding mode, surface composition, electronic structure and probable chemical changes to the stoichiometric-UO2(100) [smooth-UO2(100)] and Ar+-sputtered UO2(100) [rough-UO2(100)] surfaces. Unlike UO2(111) single crystal and UO2 thin film, Ar-ion sputtering of this UO2(100) did not result in noticeable reduction of U cations. The ethanol molecule has C-C, C-H, C-O and O-H bonds, and readily donates the hydroxyl H while interacting strongly with the UO2 surfaces. Upon ethanol adsorption (saturation occurred at 0.5 ML), only ethoxy (CH3CH2O-) species is formed on smooth-UO2(100) whereas initially formed ethoxy species are partially oxidized to surface acetate (CH3COO-) on the Ar+-sputtered UO2(100) surface. All ethoxy and acetate species are removed from the surface between 600 and 700 K.en
dc.language.isoenen
dc.publisherAmerican Chemical Society (ACS)en
dc.relation.urlhttp://pubsdc3.acs.org/doi/10.1021/acs.jpcc.5b08577en
dc.titleThe Surface Reactions of Ethanol over UO2(100) Thin Filmen
dc.typeArticleen
dc.contributor.departmentSABIC - Corporate Research and Innovation Center (CRI) at KAUSTen
dc.identifier.journalThe Journal of Physical Chemistry Cen
dc.contributor.institutionThe Department of Chemistry, Brookhaven National Laboratory, Upton, New York 11973en
dc.contributor.institutionCSE Electrochemical Energy Storage Department, Argonne National Laboratory, Argonne, Illinois 60439en
dc.contributor.institutionCenter for Functional Nanomaterials, Brookhaven National Laboratory, Upton, New York 11973en
kaust.authorIdriss, H.en
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