How Adsorbed Oxygen Atoms Inhibit Hydrogen Dissociation on Tungsten Surfaces
| Autor: | A. Rodríguez-Fernández, L. Bonnet, P. Larrégaray, R. Díez Muiño |
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| Přispěvatelé: | Université de Bordeaux, Agence Nationale de la Recherche (France), Eusko Jaurlaritza, Universidad del País Vasco, Ministerio de Ciencia, Innovación y Universidades (España), Agencia Estatal de Investigación (España) |
| Rok vydání: | 2023 |
| Předmět: | |
| Zdroj: | The Journal of Physical Chemistry Letters. 14:1246-1252 |
| ISSN: | 1948-7185 2019-1073 |
| DOI: | 10.1021/acs.jpclett.2c03684 |
| Popis: | Hydrogen molecules dissociate on clean W(110) surfaces. This reaction is progressively inhibited as the tungsten surface is precovered with oxygen. We use density functional theory and ab initio molecular dynamics to rationalize, at the atomic scale, the influence of the adsorbed O atoms on the H2 dissociation process. The reaction probability is calculated for kinetic energies below 300 meV and different O nominal coverages. We show that the adsorbed O atoms act as repulsive centers that modulate the dynamics of the impinging H2 molecules by closing dissociation pathways. In agreement with existing experimental information, H2 dissociation is absent for an O coverage of half a monolayer. The results show that the influence of O adsorbates on the dissociation dynamics on W(110) goes much beyond the blocking of possible H adsorption sites. Adsorbed O atoms create a sort of chemical shield at the surface that prevents further approach and dissociation of the H2 molecules. A.R.F. acknowledges financial support by the University of Bordeaux. This work was conducted in the scope of the transborder joint Laboratory “QuantumChemPhys: Theoretical Chemistry and Physics at the Quantum Scale” (ANR-10-IDEX-03-02). This work has been supported in part by the Basque Departamento de Educación, Universidades e Investigación, the University of the Basque Country UPV/EHU (Grant IT1246-19) and the Spanish Ministerio de Ciencia e Innovación (PID2019-107396GB-I00/AEI/10.13039/501100011033). |
| Databáze: | OpenAIRE |
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