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Adsorption and Reactions of Carbon Monoxide and Oxygen on Bare and Au-Decorated Carburized W(110)
[Image: see text] Adsorption and coadsorption of carbon monoxide and oxygen on different types of Au clusters on R(15 × 3)C/W(110) and R(15 × 12)C/W(110), respectively, are studied with respect to the catalytic behavior for oxidation of CO as well as of surface carbon. Carburization of the W(110) su...
Autores principales: | , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
American Chemical Society
2013
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Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3753032/ https://www.ncbi.nlm.nih.gov/pubmed/23991229 http://dx.doi.org/10.1021/jp404528p |
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author | Bachmann, Magdalena Bikaljevic, Djuro Memmel, Norbert Bertel, Erminald |
author_facet | Bachmann, Magdalena Bikaljevic, Djuro Memmel, Norbert Bertel, Erminald |
author_sort | Bachmann, Magdalena |
collection | PubMed |
description | [Image: see text] Adsorption and coadsorption of carbon monoxide and oxygen on different types of Au clusters on R(15 × 3)C/W(110) and R(15 × 12)C/W(110), respectively, are studied with respect to the catalytic behavior for oxidation of CO as well as of surface carbon. Carburization of the W(110) surface results in a weakening of the adsorption bond for molecularly adsorbed CO. Dissociation of carbon monoxide, which occurs on W(110), is reduced on the low-carbon coverage R(15 × 12) surface and completely suppressed on the carbon-saturated R(15 × 3) phase. Deposition of gold results in a blocking of adsorption sites for molecularly adsorbed CO and reopening of the dissociation channel. Probably the latter is associated with the existence of double-layer gold clusters and islands. At room temperature the gold clusters on both carburized templates are stable in CO atmosphere as shown by in-situ STM measurements. In contrast, exposure to oxygen alters the clusters on the R(15 × 12) surface, implying dissociation of oxygen not only on the substrate but also on or in immediate vicinity of the gold clusters. On the Au-free carburized templates oxygen adsorbs dissociatively and is released as CO at temperatures beyond 800 K due to reaction with carbon atoms from the templates. Deposition of gold enhances the desorption rate of the formed CO at the low-temperature end of the recombinative CO desorption range, indicating a promoting effect of gold for oxidation of surface carbon. In contrast, low-temperature CO oxidation catalyzed by the deposited Au clusters is not observed. Two reasons could be identified: (1) weakly bound CO with desorption temperatures between 100 and 200 K (as reported for other related systems) is not observed, and (2) oxygen atoms are bonded too strongly to the templates. |
format | Online Article Text |
id | pubmed-3753032 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2013 |
publisher | American Chemical Society |
record_format | MEDLINE/PubMed |
spelling | pubmed-37530322013-08-27 Adsorption and Reactions of Carbon Monoxide and Oxygen on Bare and Au-Decorated Carburized W(110) Bachmann, Magdalena Bikaljevic, Djuro Memmel, Norbert Bertel, Erminald J Phys Chem C Nanomater Interfaces [Image: see text] Adsorption and coadsorption of carbon monoxide and oxygen on different types of Au clusters on R(15 × 3)C/W(110) and R(15 × 12)C/W(110), respectively, are studied with respect to the catalytic behavior for oxidation of CO as well as of surface carbon. Carburization of the W(110) surface results in a weakening of the adsorption bond for molecularly adsorbed CO. Dissociation of carbon monoxide, which occurs on W(110), is reduced on the low-carbon coverage R(15 × 12) surface and completely suppressed on the carbon-saturated R(15 × 3) phase. Deposition of gold results in a blocking of adsorption sites for molecularly adsorbed CO and reopening of the dissociation channel. Probably the latter is associated with the existence of double-layer gold clusters and islands. At room temperature the gold clusters on both carburized templates are stable in CO atmosphere as shown by in-situ STM measurements. In contrast, exposure to oxygen alters the clusters on the R(15 × 12) surface, implying dissociation of oxygen not only on the substrate but also on or in immediate vicinity of the gold clusters. On the Au-free carburized templates oxygen adsorbs dissociatively and is released as CO at temperatures beyond 800 K due to reaction with carbon atoms from the templates. Deposition of gold enhances the desorption rate of the formed CO at the low-temperature end of the recombinative CO desorption range, indicating a promoting effect of gold for oxidation of surface carbon. In contrast, low-temperature CO oxidation catalyzed by the deposited Au clusters is not observed. Two reasons could be identified: (1) weakly bound CO with desorption temperatures between 100 and 200 K (as reported for other related systems) is not observed, and (2) oxygen atoms are bonded too strongly to the templates. American Chemical Society 2013-07-24 2013-08-22 /pmc/articles/PMC3753032/ /pubmed/23991229 http://dx.doi.org/10.1021/jp404528p Text en Copyright © 2013 American Chemical Society Terms of Use (http://pubs.acs.org/page/policy/authorchoice_termsofuse.html) |
spellingShingle | Bachmann, Magdalena Bikaljevic, Djuro Memmel, Norbert Bertel, Erminald Adsorption and Reactions of Carbon Monoxide and Oxygen on Bare and Au-Decorated Carburized W(110) |
title | Adsorption and Reactions of Carbon Monoxide and Oxygen
on Bare and Au-Decorated Carburized W(110) |
title_full | Adsorption and Reactions of Carbon Monoxide and Oxygen
on Bare and Au-Decorated Carburized W(110) |
title_fullStr | Adsorption and Reactions of Carbon Monoxide and Oxygen
on Bare and Au-Decorated Carburized W(110) |
title_full_unstemmed | Adsorption and Reactions of Carbon Monoxide and Oxygen
on Bare and Au-Decorated Carburized W(110) |
title_short | Adsorption and Reactions of Carbon Monoxide and Oxygen
on Bare and Au-Decorated Carburized W(110) |
title_sort | adsorption and reactions of carbon monoxide and oxygen
on bare and au-decorated carburized w(110) |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3753032/ https://www.ncbi.nlm.nih.gov/pubmed/23991229 http://dx.doi.org/10.1021/jp404528p |
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