Oxidation of Pd(553): From ultrahigh vacuum to atmospheric pressure

Author(s)

Rasmus Westerström, Johan Gustafson, Andrea Resta, Anders Mikkelsen, Jesper N. Andersen, Edvin Lundgren, Nicola Seriani, Florian Mittendorfer, Michael A. Schmid, J Klikovits, Peter Varga, M. D. Ackermann, Joost W M Frenken, N Kasper, Andreas Stierle

Abstract

The oxidation of a vicinal Pd(553) surface has been studied from

ultrahigh vacuum (UHV) to atmospheric oxygen pressures at elevated

sample temperatures. The investigation combines traditional electron

based UHV techniques such as high resolution core level spectroscopy,

low-energy electron diffraction, scanning tunneling microscopy with in situ surface x-ray diffraction, and ab initio simulations. In this way, we show that the O atoms preferentially adsorb at the step edges at oxygen pressures below 10−6mbar and that the (553) surface is preserved. In the pressure range between 10−6 and 1mbar and at a sample temperature of 300–400°C,

a surface oxide forms and rearranges the (553) surface facets and

forming (332) facets. Most of the surface oxide can be described as a

PdO(101) plane, similar to what has been found previously on other Pd

surfaces. However, in the present case, the surface oxide is

reconstructed along the step edges, and the stability of this structure

is discussed. In addition, the (6√×6√) Pd5O4 surface oxide can be observed on (111) terraces larger than those of the (332) terraces. Increasing the O pressure above 1mbar results in the disappearance of the (332) facets and the formation of PdO bulk oxide.

Organisation(s)

Computational Materials Physics

External organisation(s)

Lund University, Technische Universität Wien, Leiden University, Max-Planck-Institut für Metallforschung

Journal

Physical Review B

Volume

No. of pages

ISSN

1098-0121

DOI

https://doi.org/10.1103/PhysRevB.76.155410

Publication date

2007

Peer reviewed

Yes

Austrian Fields of Science 2012

1030 Physics, Astronomy

Portal url

https://ucrisportal.univie.ac.at/en/publications/oxidation-of-pd553-from-ultrahigh-vacuum-to-atmospheric-pressure(db9bd8af-2f68-4e1e-9e67-a4b2e5828317).html