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In Situ X-ray Absorption Spectroscopy in the Soft Energy Range: Novel Prospects for the Chemical Characterization of Solid State Surfaces at High Pressure And High Temperature

Published online by Cambridge University Press:  21 March 2011

Th. Schedel-Niedrig
Affiliation:
Hahn-Meitner-Institut Berlin GmbH, Glienicker Strasse 100, 14109 Berlin, Germany
M. Hävecker
Affiliation:
Fritz-Haber-Institut, Faradayweg 4-6, 14195 Berlin, Germany
A. Knop-Gericke
Affiliation:
Fritz-Haber-Institut, Faradayweg 4-6, 14195 Berlin, Germany
P. Reinke
Affiliation:
Universität Basel, Georg-August-Universität Gö]ttingen, II. Physikalisches Institut, Bunsenstrasse 7-9, 37073 Göttigen, Germany
R. Schlögl
Affiliation:
Fritz-Haber-Institut, Faradayweg 4-6, 14195 Berlin, Germany
M. Ch. Lux-Steiner
Affiliation:
Hahn-Meitner-Institut Berlin GmbH, Glienicker Strasse 100, 14109 Berlin, Germany
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Abstract

An instrument equipped with total electron yield detectors was designed and constructed for in situ X-ray absorption spectroscopy (XAS) investigations in the soft X-ray range (100 eV ≤ hν ≤ 1000 eV) at elevated pressures (mbar range) and sample temperatures (T ≤ 1000 K) [1]. This allows, for the first time, XAS studies in a surface-sensitive mode of the light elements (Z = 3-15). Furthermore, the gas phase XAS and the surface-related XAS of the solid state phase can be collected simultaneously in order to correlate the gas/solid reaction rate with the surface electronic structure under working conditions in a flow-through mode.

The novel experimental tool represents a contribution to the experimental overcoming of the “pressure gap” in material science. In this work examples are presented belonging to the field of heterogeneous catalysis [2-4] and to the reactivity of diamond surfaces [5]. Additionally, prospects for in situ studies in material science will be given.

Type
Research Article
Copyright
Copyright © Materials Research Society 2001

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References

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