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Structural changes in noble metal nanoparticles during CO oxidation and their impact on catalyst activity
The dynamical structure of a catalyst determines the availability of active sites on its surface. However, how nanoparticle (NP) catalysts re-structure under reaction conditions and how these changes associate with catalytic activity remains poorly understood. Using operando transmission electron mi...
Autores principales: | , , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Nature Publishing Group UK
2020
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7195460/ https://www.ncbi.nlm.nih.gov/pubmed/32358583 http://dx.doi.org/10.1038/s41467-020-16027-9 |
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author | Chee, See Wee Arce-Ramos, Juan Manuel Li, Wenqing Genest, Alexander Mirsaidov, Utkur |
author_facet | Chee, See Wee Arce-Ramos, Juan Manuel Li, Wenqing Genest, Alexander Mirsaidov, Utkur |
author_sort | Chee, See Wee |
collection | PubMed |
description | The dynamical structure of a catalyst determines the availability of active sites on its surface. However, how nanoparticle (NP) catalysts re-structure under reaction conditions and how these changes associate with catalytic activity remains poorly understood. Using operando transmission electron microscopy, we show that Pd NPs exhibit reversible structural and activity changes during heating and cooling in mixed gas environments containing O(2) and CO. Below 400 °C, the NPs form flat low index facets and are inactive towards CO oxidation. Above 400 °C, the NPs become rounder, and conversion of CO to CO(2) increases significantly. This behavior reverses when the temperature is later reduced. Pt and Rh NPs under similar conditions do not exhibit such reversible transformations. We propose that adsorbed CO molecules suppress the activity of Pd NPs at lower temperatures by stabilizing low index facets and reducing the number of active sites. This hypothesis is supported by thermodynamic calculations. |
format | Online Article Text |
id | pubmed-7195460 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2020 |
publisher | Nature Publishing Group UK |
record_format | MEDLINE/PubMed |
spelling | pubmed-71954602020-05-05 Structural changes in noble metal nanoparticles during CO oxidation and their impact on catalyst activity Chee, See Wee Arce-Ramos, Juan Manuel Li, Wenqing Genest, Alexander Mirsaidov, Utkur Nat Commun Article The dynamical structure of a catalyst determines the availability of active sites on its surface. However, how nanoparticle (NP) catalysts re-structure under reaction conditions and how these changes associate with catalytic activity remains poorly understood. Using operando transmission electron microscopy, we show that Pd NPs exhibit reversible structural and activity changes during heating and cooling in mixed gas environments containing O(2) and CO. Below 400 °C, the NPs form flat low index facets and are inactive towards CO oxidation. Above 400 °C, the NPs become rounder, and conversion of CO to CO(2) increases significantly. This behavior reverses when the temperature is later reduced. Pt and Rh NPs under similar conditions do not exhibit such reversible transformations. We propose that adsorbed CO molecules suppress the activity of Pd NPs at lower temperatures by stabilizing low index facets and reducing the number of active sites. This hypothesis is supported by thermodynamic calculations. Nature Publishing Group UK 2020-05-01 /pmc/articles/PMC7195460/ /pubmed/32358583 http://dx.doi.org/10.1038/s41467-020-16027-9 Text en © The Author(s) 2020 Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. |
spellingShingle | Article Chee, See Wee Arce-Ramos, Juan Manuel Li, Wenqing Genest, Alexander Mirsaidov, Utkur Structural changes in noble metal nanoparticles during CO oxidation and their impact on catalyst activity |
title | Structural changes in noble metal nanoparticles during CO oxidation and their impact on catalyst activity |
title_full | Structural changes in noble metal nanoparticles during CO oxidation and their impact on catalyst activity |
title_fullStr | Structural changes in noble metal nanoparticles during CO oxidation and their impact on catalyst activity |
title_full_unstemmed | Structural changes in noble metal nanoparticles during CO oxidation and their impact on catalyst activity |
title_short | Structural changes in noble metal nanoparticles during CO oxidation and their impact on catalyst activity |
title_sort | structural changes in noble metal nanoparticles during co oxidation and their impact on catalyst activity |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7195460/ https://www.ncbi.nlm.nih.gov/pubmed/32358583 http://dx.doi.org/10.1038/s41467-020-16027-9 |
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