Lattice gas study of the kinetics of the NO-CO catalytic reaction on Pd nanoclusters

The kinetics of the NO-CO reaction on Pd nanoclusters is studied through a lattice-gas model and Monte Carlo simulation. Pd nanoclusters with three typical sizes: 2.8 nm, 6.9 nm and 15.6 nm, are considered. These nanoclusters have been epitaxially grown on MgO(100) and tested for the NO-CO reaction...

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Detalles Bibliográficos
Autores: Bustos Giunta, Victor Angel, Uñac, Rodolfo Omar, Zgrablich, Giorgio, Henry, Claude R.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2003
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/136297
Acceso en línea:http://hdl.handle.net/11336/136297
Access Level:acceso abierto
Palabra clave:CATALYTIC REACTION
PD NANOCLUSTER
https://purl.org/becyt/ford/1.3
https://purl.org/becyt/ford/1
Descripción
Sumario:The kinetics of the NO-CO reaction on Pd nanoclusters is studied through a lattice-gas model and Monte Carlo simulation. Pd nanoclusters with three typical sizes: 2.8 nm, 6.9 nm and 15.6 nm, are considered. These nanoclusters have been epitaxially grown on MgO(100) and tested for the NO-CO reaction in previous experimental work [ref. 9-11: C. H. F. Peden, D. W. Goodman, D. S. Blair, P. J. Berlowitz, G. B. Fisher and S. H. Oh, J. Phys. Chem., 1988, 92, 1563; C. Duriez, C. R. Henry and C. Chapon, Surf. Sci., 1991, 253, 190; L. Piccolo and C. R. Henry, Appl. Surf. Sci., 2000, 162-163, 670], thus providing the motivation for the present study. According to their size, the nanoclusters present different proportions of Pd(100) and Pd(111) facets. The effects of CO and NO desorption are found to be of fundamental importance for the behavior of the system. In all cases the medium size particles are found to be the most active. At low temperature, where NO desorption can be neglected (since the activation energy for desorption of NO on Pd is about 5 kcal mol-1 greater than that for the desorption of CO), the largest particles are revealed as the less active, while at high temperature, where both NO and CO desorption take place, the smallest particles are found to be the less active. These results are in concordance with the experimentally observed behavior.