Effect of particle morphology on the ripening of supported Pt nanoparticles
Journal article, 2012
To improve the understanding of sintering in diesel and lean-burn engine exhaust aftertreatment catalysts, we examined oxygen-induced sintering in a model catalyst consisting of Pt nanoparticles supported on a planar, amorphous Al2O3 substrate. After ageing at increasing
temperatures, transmission electron microscopy analysis reveals that highly monodisperse ensembles of nanoparticles transformed into ensembles with bimodal and subsequently Lifshitz-Slyozov-Wagner particle size distributions. Moreover, scanning transmission electron microscopy and atomic force microscopy analysis suggest that the Pt nanoparticles have size-dependent morphologies after sintering in oxidizing environment. The evolution of the particle sizes is described by a simple kinetic model for ripening and the size-dependent particle morphology is proposed as an explanation for the observed bimodal particle size distribution shapes.
Ostwald ripening
AFM
catalyst
sintering
STEM
Pt/Al2O3
TEM
Author
S. B. Simonsen
Haldor Topsoe A/S
Danmarks Tekniske Universitet
Ib Chorkendorff
Danmarks Tekniske Universitet
Søren Dahl
Danmarks Tekniske Universitet
Magnus Skoglundh
Competence Centre for Catalysis (KCK)
Chalmers, Chemical and Biological Engineering, Applied Surface Chemistry
Kristoffer Meinander
Aarhus Universitet
Thomas Nørregaard Jensen
Aarhus Universitet
Jeppe Lauritsen
Aarhus Universitet
Stig Helveg
Haldor Topsoe A/S
Journal of Physical Chemistry C
1932-7447 (ISSN) 1932-7455 (eISSN)
Vol. 116 9 5646-5653Driving Forces
Sustainable development
Areas of Advance
Nanoscience and Nanotechnology
Transport
Energy
Materials Science
Subject Categories (SSIF 2011)
Chemical Engineering
DOI
10.1021/jp2098262