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arXiv · 1804.07631

Ethanol chemisorption on core-shell Pt-nanoparticles: an ab-initio study

Vagner A. Rigo·Caetano R. Miranda·Francesca Baletto
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Abstract

By means of ab-initio calculations, we have investigated the chemisorption paroperties of ethanol onto segregating binary nanoalloys. We select nanostructures with icosahedral shape of 55 atoms with a Pt outermost layer over a M core with M=Ag,Pd,Ni. With respect to nanofilms with equivalent composition, there is an increse of the ethanol binding energy. This is not merely due to observed shortening of the Pt-O distance but depends on the nanoparticle distortion after ethanol adsorption. This geometrical distortion within the nanoparticle can be interpreted as a radial breathing, which is sensitive to the adsortion site, identified by the O-anchor point and the relative positions of the ethyl group. More interestingly, being core-dependent -larger in Pd@Pt and smaller in Ni@Pt-, it relates to an effective electron transfer from ethanol and the M-core towards the Pt-shell. On the view of this new analysis, Pd@Pt nanoalloys show the most promissing features for ethanol oxidation.

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Vagner A. Rigo, Caetano R. Miranda, Francesca Baletto. 2018-04-20. Ethanol chemisorption on core-shell Pt-nanoparticles: an ab-initio study. https://doi.org/10.1140/epjb%2Fe2018-90241-3

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