The Origin of the Size Effect in the Oxidation of CO on Supported Palladium Nanoparticles
Two Pd/TiO<sub>2</sub> catalysts with mean particle sizes of 1 and 3 nm were prepared and tested in the low-temperature oxidation of CO. It was found that the first catalyst with higher dispersion is more active. Turnover frequencies varied for these catalysts by almost six times. In con...
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MDPI AG
2023-11-01
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| Series: | Catalysts |
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| Online Access: | https://www.mdpi.com/2073-4344/13/11/1435 |
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| author | Vasily V. Kaichev Andrey A. Saraev Aleksandr V. Fedorov Evgeny Yu. Gerasimov |
| author_facet | Vasily V. Kaichev Andrey A. Saraev Aleksandr V. Fedorov Evgeny Yu. Gerasimov |
| author_sort | Vasily V. Kaichev |
| collection | DOAJ |
| description | Two Pd/TiO<sub>2</sub> catalysts with mean particle sizes of 1 and 3 nm were prepared and tested in the low-temperature oxidation of CO. It was found that the first catalyst with higher dispersion is more active. Turnover frequencies varied for these catalysts by almost six times. In contrast, the apparent activation energy of the oxidation of CO on the catalyst with smaller Pd nanoparticles was estimated at 76 kJ/mol, and for the catalyst with larger Pd nanoparticles at 58 kJ/mol. According to in situ XANES studies, the particle size effect originates from the oxidation of small palladium nanoparticles under reaction conditions, whereas larger nanoparticles are stable and consist of palladium atoms mainly in the metallic state. Palladium oxide is more active in the low-temperature oxidation of CO than metallic palladium. This means that the origin of size-dependent activity of Pd nanoparticles in the low-temperature oxidation of CO is associated with the change in the chemical composition of nanoparticles that leads to a change in the reaction mechanism and, as a result, in their activity. |
| first_indexed | 2024-03-09T16:56:54Z |
| format | Article |
| id | doaj.art-a0f62522776549c9bccabf6a8457747d |
| institution | Directory Open Access Journal |
| issn | 2073-4344 |
| language | English |
| last_indexed | 2024-03-09T16:56:54Z |
| publishDate | 2023-11-01 |
| publisher | MDPI AG |
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| series | Catalysts |
| spelling | doaj.art-a0f62522776549c9bccabf6a8457747d2023-11-24T14:35:03ZengMDPI AGCatalysts2073-43442023-11-011311143510.3390/catal13111435The Origin of the Size Effect in the Oxidation of CO on Supported Palladium NanoparticlesVasily V. Kaichev0Andrey A. Saraev1Aleksandr V. Fedorov2Evgeny Yu. Gerasimov3Department of Catalyst Research, Boreskov Institute of Catalysis, Novosibirsk 630090, RussiaDepartment of Catalyst Research, Boreskov Institute of Catalysis, Novosibirsk 630090, RussiaDepartment of Catalyst Discovery and Reaction Engineering, Leibniz-Institut für Katalyse e.V., 18059 Rostock, GermanyDepartment of Catalyst Research, Boreskov Institute of Catalysis, Novosibirsk 630090, RussiaTwo Pd/TiO<sub>2</sub> catalysts with mean particle sizes of 1 and 3 nm were prepared and tested in the low-temperature oxidation of CO. It was found that the first catalyst with higher dispersion is more active. Turnover frequencies varied for these catalysts by almost six times. In contrast, the apparent activation energy of the oxidation of CO on the catalyst with smaller Pd nanoparticles was estimated at 76 kJ/mol, and for the catalyst with larger Pd nanoparticles at 58 kJ/mol. According to in situ XANES studies, the particle size effect originates from the oxidation of small palladium nanoparticles under reaction conditions, whereas larger nanoparticles are stable and consist of palladium atoms mainly in the metallic state. Palladium oxide is more active in the low-temperature oxidation of CO than metallic palladium. This means that the origin of size-dependent activity of Pd nanoparticles in the low-temperature oxidation of CO is associated with the change in the chemical composition of nanoparticles that leads to a change in the reaction mechanism and, as a result, in their activity.https://www.mdpi.com/2073-4344/13/11/1435heterogeneous catalysissize effectnanoparticlespalladiumCO oxidation |
| spellingShingle | Vasily V. Kaichev Andrey A. Saraev Aleksandr V. Fedorov Evgeny Yu. Gerasimov The Origin of the Size Effect in the Oxidation of CO on Supported Palladium Nanoparticles Catalysts heterogeneous catalysis size effect nanoparticles palladium CO oxidation |
| title | The Origin of the Size Effect in the Oxidation of CO on Supported Palladium Nanoparticles |
| title_full | The Origin of the Size Effect in the Oxidation of CO on Supported Palladium Nanoparticles |
| title_fullStr | The Origin of the Size Effect in the Oxidation of CO on Supported Palladium Nanoparticles |
| title_full_unstemmed | The Origin of the Size Effect in the Oxidation of CO on Supported Palladium Nanoparticles |
| title_short | The Origin of the Size Effect in the Oxidation of CO on Supported Palladium Nanoparticles |
| title_sort | origin of the size effect in the oxidation of co on supported palladium nanoparticles |
| topic | heterogeneous catalysis size effect nanoparticles palladium CO oxidation |
| url | https://www.mdpi.com/2073-4344/13/11/1435 |
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