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Materialien/Werkstoffe Poster: Do., 13:00–15:30 D-P405
Structural characterization of LaMn1−xPdxO3-Perovskites by in-situ Synchrotron
powder diffraction-experiments
D. Stürmer 1 , C. Baehtz 2 , L. Giebeler 1 , H. Fuess 1
1 Institute of Materials Science, Darmstadt University of Technology, D-64287 Darmstadt
– 2 HASYLAB Hamburg, Notkestr. 85, D-22607 Hamburg, Germany
Perovskite-type oxides have interesting catalytic properties e.g. for the total oxidation
of hydrocarbons [1]. These catalytic properties can be improved, by replacing parts
of the manganese by noble metals like palladium. In the past few years LaFeO3 perovskites
doped with palladium were found to be a good alternative to Al2O3-supported
Pt catalysts for automotive exhaust applications [2].
A furnace working in capillary geometry designated for diffraction experiments under
controlled atmosphere was used to examine the formation of the Perovskite from
the precursor, which was prepared by the Pechini method. The calcined perovskite
was later once treated with oxygen and afterwards with hydrogen. Hereby a phase
transformation is observed, which is also stable under oxygen atmosphere. Samples
with different palladium content were investigated The aim of this experiment was to
determine the structural changes during the catalyst preparation and catalysis.
This work was financially supported by the virtual institute VH-VI-102, Development
of in-situ characterization techniques for polycrystalline materials using high energy
synchrotron radiation, of the Helmholtz Gemeinschaft.
[1] M. A. Peña et al., Chem. Rev., 101, (2001) 1981-2017
[2] H. Tanaka et al., Top. Catal., 30/31, (2004) 389-396