Regensburg 2010 – wissenschaftliches Programm
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KR: Fachverband Kristallographie
KR 2: Crystallography in nanoscience
KR 2.10: Vortrag
Dienstag, 23. März 2010, 12:30–12:45, H9
Microstructure study of gold-zirconia yolk-shell nanostructures using XRD line profile analysis — •Arti Dangwal Pandey1, Robert Güttel1, Matteo Leoni2, Ferdi Schüth1, and Claudia Weidenthaler1 — 1Max-Planck-Institut für Kohlenforschung, Mülheim (Ruhr), Germany — 2University of Trento, Italy
The detailed microstructure study of gold nanoparticles encapsulated inside crystalline zirconia hollow-spheres is presented. This system is a potential nano-catalyst for CO-oxidation such as in automotive exhaust gas treatment.[1] The crystalline zirconia shell of 200 nm diameter separates the 15 nm gold nanoparticles from each other and provides high temperature stability to this system. To retrieve the microstructure details like size distribution, dislocation density, dislocation character, and defect content from the powder diffraction data of this two phase nanostructure system, we used whole powder pattern modeling (WPPM) for line profile analysis [2]. A series of diffraction and microscopic measurements were performed to investigate how the microstructure of these nanostructures evolves after some chemical and heat treatments. The observed variation in the crystallite size and defect contents after gold-leaching or quenching of the as prepared material from 900°C will be discussed in detail and the influence on the catalytic activity of gold nanoparticles will be presented.
1. P.M. Arnal, M. Comotti and F. Schüth, Angew. Chem. Int. Ed., 2006, 45, 8224.
2. Scardi P. and Leoni M., Acta Cryst. A, 2002, 58, 190-200.