Journal article
Catalyst Chemical State during CO Oxidation Reaction on Cu(111) Studied with Ambient-Pressure X-ray Photoelectron Spectroscopy and Near Edge X-ray Adsorption Fine Structure Spectroscopy
Journal of the American Chemical Society, Vol.137(34), pp.11186-11190
02/Sep/2015
Abstract
The chemical structure of a Cu(111) model catalyst during the CO oxidation reaction in the CO+O-2 pressure range of 10-300 mTorr at 298-413 K was studied in situ using surface sensitive X-ray photoelectron and adsorption spectroscopy techniques [X-ray photoelectron spectroscopy (XPS) and near edge X-ray adsorption fine structure spectroscopy (NEXAFS)]. For O-2:CO partial pressure ratios below 1:3, the surface is covered by chemisorbed O and by a thin (similar to 1 nm) Cu2O layer, which covers completely the surface for ratios above 1:3 between 333 and 413 K. The Cu2O film increases in thickness and exceeds the escape depth (similar to 3-4 nm) of the XPS and NEXAFS photoelectrons used for analysis at 413 K. No CuO formation was detected under the reaction conditions used in this work. The main reaction intermediate was found to be CO2 delta-, with a coverage that correlates with the amount of Cu2O, suggesting that this phase is the most active for CO oxidation.
Details
- Title
- Catalyst Chemical State during CO Oxidation Reaction on Cu(111) Studied with Ambient-Pressure X-ray Photoelectron Spectroscopy and Near Edge X-ray Adsorption Fine Structure Spectroscopy
- Creators
- Baran Eren (null) - Lawrence Berkeley National LaboratoryChristian Heine (null)Hendrik Bluhm (null)Gabor A. Somorjai (null)Miguel Salmeron (Corresponding Author) - University of California, Berkeley
- Resource Type
- Journal article
- Publication Details
- Journal of the American Chemical Society, Vol.137(34), pp.11186-11190; 02/Sep/2015
- Number of pages
- 5
- Language
- English
- DOI
- https://doi.org/10.1021/jacs.5b07451
- Grant note
- Office of Basic Energy Sciences (BES), Division of Materials Sciences and Engineering, of the U.S. Department of Energy (DOE through Chemical and Mechanical Properties of Surfaces, Interfaces and Nanostructures program [DE-AC02-05CH11231]; Office of BES, Division of Chemical Sciences, Geosciences and Biosciences, of the U.S. DOE This work was supported by the Office of Basic Energy Sciences (BES), Division of Materials Sciences and Engineering, of the U.S. Department of Energy (DOE) via Contract DE-AC02-05CH11231, through the Chemical and Mechanical Properties of Surfaces, Interfaces and Nanostructures program. H.B. acknowledges support from the Office of BES, Division of Chemical Sciences, Geosciences and Biosciences, of the U.S. DOE._ALMAME_DELIMITER_
- Record Identifier
- 993263858503596
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