N<sub>2</sub>O Hydrogenation on Silver Doped Gold Catalysts, a DFT Study
In this study, the full reaction mechanism for N<sub>2</sub>O hydrogenation on silver doped Au(210) surfaces was investigated in order to clarify the experimental observations. Density functional theory (DFT) calculations were used to state the most favorable reaction paths for individua...
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| Format: | Article |
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MDPI AG
2022-01-01
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| Series: | Nanomaterials |
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| Online Access: | https://www.mdpi.com/2079-4991/12/3/394 |
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| author | José L. C. Fajín Maria Natália D. S. Cordeiro |
| author_facet | José L. C. Fajín Maria Natália D. S. Cordeiro |
| author_sort | José L. C. Fajín |
| collection | DOAJ |
| description | In this study, the full reaction mechanism for N<sub>2</sub>O hydrogenation on silver doped Au(210) surfaces was investigated in order to clarify the experimental observations. Density functional theory (DFT) calculations were used to state the most favorable reaction paths for individual steps involved in the N<sub>2</sub>O hydrogenation. From the DFT results, the activation energy barriers, rate constants and reaction energies for the individual steps were determined, which made it possible to elucidate the most favorable reaction mechanism for the global catalytic process. It was found that the N<sub>2</sub>O dissociation occurs in surface regions where silver atoms are present, while hydrogen dissociation occurs in pure gold regions of the catalyst or in regions with a low silver content. Likewise, N<sub>2</sub>O dissociation is the rate determining step of the global process, while water formation from O adatoms double hydrogenation and N<sub>2</sub> and H<sub>2</sub>O desorptions are reaction steps limited by low activation energy barriers, and therefore, the latter are easily carried out. Moreover, water formation occurs in the edges between the regions where hydrogen and N<sub>2</sub>O are dissociated. Interestingly, a good dispersion of the silver atoms in the surface is necessary to avoid catalyst poison by O adatoms accumulation, which are strongly adsorbed on the surface. |
| first_indexed | 2024-03-09T23:24:43Z |
| format | Article |
| id | doaj.art-b5dcc50c82cc4f4386feef35dd4831da |
| institution | Directory Open Access Journal |
| issn | 2079-4991 |
| language | English |
| last_indexed | 2024-03-09T23:24:43Z |
| publishDate | 2022-01-01 |
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| series | Nanomaterials |
| spelling | doaj.art-b5dcc50c82cc4f4386feef35dd4831da2023-11-23T17:20:05ZengMDPI AGNanomaterials2079-49912022-01-0112339410.3390/nano12030394N<sub>2</sub>O Hydrogenation on Silver Doped Gold Catalysts, a DFT StudyJosé L. C. Fajín0Maria Natália D. S. Cordeiro1LAQV@REQUIMTE, Department of Chemistry and Biochemistry, Faculty of Sciences, University of Porto, P-4169-007 Porto, PortugalLAQV@REQUIMTE, Department of Chemistry and Biochemistry, Faculty of Sciences, University of Porto, P-4169-007 Porto, PortugalIn this study, the full reaction mechanism for N<sub>2</sub>O hydrogenation on silver doped Au(210) surfaces was investigated in order to clarify the experimental observations. Density functional theory (DFT) calculations were used to state the most favorable reaction paths for individual steps involved in the N<sub>2</sub>O hydrogenation. From the DFT results, the activation energy barriers, rate constants and reaction energies for the individual steps were determined, which made it possible to elucidate the most favorable reaction mechanism for the global catalytic process. It was found that the N<sub>2</sub>O dissociation occurs in surface regions where silver atoms are present, while hydrogen dissociation occurs in pure gold regions of the catalyst or in regions with a low silver content. Likewise, N<sub>2</sub>O dissociation is the rate determining step of the global process, while water formation from O adatoms double hydrogenation and N<sub>2</sub> and H<sub>2</sub>O desorptions are reaction steps limited by low activation energy barriers, and therefore, the latter are easily carried out. Moreover, water formation occurs in the edges between the regions where hydrogen and N<sub>2</sub>O are dissociated. Interestingly, a good dispersion of the silver atoms in the surface is necessary to avoid catalyst poison by O adatoms accumulation, which are strongly adsorbed on the surface.https://www.mdpi.com/2079-4991/12/3/394N<sub>2</sub>O eliminationgreenhouse effectbimetallic catalystsheterogeneous catalysisDFT calculations discipline |
| spellingShingle | José L. C. Fajín Maria Natália D. S. Cordeiro N<sub>2</sub>O Hydrogenation on Silver Doped Gold Catalysts, a DFT Study Nanomaterials N<sub>2</sub>O elimination greenhouse effect bimetallic catalysts heterogeneous catalysis DFT calculations discipline |
| title | N<sub>2</sub>O Hydrogenation on Silver Doped Gold Catalysts, a DFT Study |
| title_full | N<sub>2</sub>O Hydrogenation on Silver Doped Gold Catalysts, a DFT Study |
| title_fullStr | N<sub>2</sub>O Hydrogenation on Silver Doped Gold Catalysts, a DFT Study |
| title_full_unstemmed | N<sub>2</sub>O Hydrogenation on Silver Doped Gold Catalysts, a DFT Study |
| title_short | N<sub>2</sub>O Hydrogenation on Silver Doped Gold Catalysts, a DFT Study |
| title_sort | n sub 2 sub o hydrogenation on silver doped gold catalysts a dft study |
| topic | N<sub>2</sub>O elimination greenhouse effect bimetallic catalysts heterogeneous catalysis DFT calculations discipline |
| url | https://www.mdpi.com/2079-4991/12/3/394 |
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