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CO dissociation and CO+O reactions on a nanosized iron cluster

Lanzani, Giorgio and Nasibulin, Albert G. and Laasonen, Kari and Kauppinen, Esko I. (2009) CO dissociation and CO+O reactions on a nanosized iron cluster. Nano Research, 2 (8). pp. 660-670.

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Abstract

Catalysis over metal nanoparticles is essential for the growth of carbon nanotubes and all the properties of the resulting nanotube, such as diameter and chirality, are affected by the metal particle. Thus, it is very important to understand the carbon chemistry taking place on nanometer size metal particles. Here we present the first ab initio computational study of chemical reactions on a nanosized iron cluster. The clusters have reaction sites, such as edges and vertexes between the facets, Which have not been studied before. First principles electronic structure calculations, fully incorporating the effects of spin polarization and non-collinear magnetic moments, have been used to investigate CO disproportionation on an isolated Fe55 cluster. After CO dissociation, O atoms remain on the surface while C atoms move into the cluster, presumably as the initial step toward carbide formation. Here we show that the lowest CO dissociation barrier found on the cluster (0.77 eV) is lower than on most previously studied Fe surfaces. This dissociation occurs on a vertex between the facets. Several possible paths for CO2 formation were identified. The calculated lowest reaction barrier is 1.08 eV, which is comparable to the barrier of 0.65 eV obtained by experiment.

Item Type:Article
Uncontrolled Keywords:Nanoparticle - density functional theory (DFT) - mechanism - synthesis
Subjects:Material Science > Nanofabrication processes and tools
Material Science > Nanochemistry
ID Code:6903
Deposited By:Lesley Tobin
Deposited On:14 Aug 2009 13:56
Last Modified:14 Aug 2009 13:56

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