Journal article
Structure sensitivity for NO dissociation on palladium and rhodium surfaces
Institut de Recherches sur la Catalyse, Centre National de la Recherche Scientifique, 2 Avenue Albert Einstein, F-69626 Villeurbanne cedex, France
Laboratoire de Chimie Théorique et des Matériaux Hybrides, École Normale Supérieure de Lyon, 46 Allée d'Italie, F-69364 Lyon cedex 07, France
We present a comparative density-functional theory study of the chemisorption and the dissociation of the NO molecule on the close-packed (111), the more open (100), and the stepped (511) surfaces of palladium and rhodium. The energetic and kinetic properties of the reaction pathways are reported. The structure sensitivity is correlated to the catalytic activity, which can be linked to the calculated dissociation rate constants at 300 K: Rh (100)⩾terrace Rh (511)>step Rh (511)>step Pd (511)>Rh (111)>Pd (100)⩾terrace Pd (511)>Pd (111).
The effect of the steps on the activity is found to be clearly favorable for the Pd (511) surface and unfavorable for the Rh (511) surface. The reaction barriers are correlated to the stability of the final states and the geometries of the molecular precursor states.
Language: | English |
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Year: | 2002 |
Pages: | 211-225 |
ISSN: | 10902694 and 00219517 |
Types: | Journal article |
DOI: | 10.1016/S0021-9517(02)00030-1 |