A first-principles study of bulk oxide formation on Pd (100)

Autor(en)

Nicola Seriani, Judith Harl, Florian Mittendorfer, Georg Kresse

Abstrakt

The catalytic oxidation activity of palladium is influenced by the oxidation state of the metal. Under technologically relevant conditions, bulk and surface oxides may form and decompose. By employing first-principles calculations based on density functional theory, we have investigated the transition from the surface oxide to the bulk oxide on Pd(100). We show that the most stable orientation of the oxide film is PdO(101)@Pd(100) at any film thickness. The monolayer has unique electronic, chemical, and thermodynamic properties in comparison to thicker oxide films. In particular, carbon monoxide adsorbs by similar to 0.3 eV more strongly on thicker oxides than on the surface oxide, a fact that should influence the catalytical activity. Finally, we show that a simple model employing density functional theory energies predicts a Stranski-Krastanov growth mode for the oxide film, with a critical thickness of 1 ML. Our results give a framework for the interpretation of experiments of Pd oxide growth.

Organisation(en)

Computergestützte Materialphysik

Journal

Journal of Chemical Physics

Band

131

Anzahl der Seiten

7

ISSN

0021-9606

DOI

https://doi.org/10.1063/1.3187935

Publikationsdatum

2009

Peer-reviewed

Ja

ÖFOS 2012

103009 Festkörperphysik, 103015 Kondensierte Materie, 103025 Quantenmechanik, 103036 Theoretische Physik

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/42000c93-e91a-4f8b-ab02-3c3b1c9eba98