Journalartikel

Jahr der Veröffentlichung: 2008

Seiten: 184017-184040

Zeitschrift: Journal of Physics: Condensed Matter

Bandnummer: 20

Heftnummer: 18

DOI Link: https://doi.org/10.1088/0953-8984/20/18/184017

Verlag: IOP Publishing

Abstract: 

It is shown that both the materials and the pressure gaps can be bridged for ruthenium in heterogeneous oxidation catalysis using the oxidation of carbon monoxide as a model reaction. Polycrystalline catalysts, such as supported Ru catalysts and micrometer-sized Ru powder, were compared to single-crystalline ultrathin RuO2 films serving as model catalysts. The microscopic reaction steps on RuO2 were identified by a combined experimental and theoretical approach applying density functional theory. Steady-state CO oxidation and transient kinetic experiments such as temperature-programmed desorption were performed with polycrystalline catalysts and single-crystal surfaces and analyzed on the basis of a microkinetic model. Infrared spectroscopy turned out to be a valuable tool allowing us to identify adsorption sites and adsorbed species under reaction conditions both for practical catalysts and for the model catalyst over a wide temperature and pressure range. The close interplay of the experimental and theoretical surface science approach with the kinetic and spectroscopic research on catalysts applied in plug–flow reactors provides a synergistic strategy for improving the performance of Ru-based catalysts. The most active and stable state was identified with an ultrathin RuO2 shell coating a metallic Ru core. The microscopic processes causing the structural deactivation of Ru-based catalysts while oxidizing CO have been identified.

Harvard-Zitierstil: Assmann, J., Narkhede, V., Breuer, N., Muhler, M., Seitsonen, A., Knapp, M., et al. (2008) Heterogeneous oxidation catalysis on ruthenium: bridging the pressure and materials gaps and beyond, Journal of Physics: Condensed Matter, 20(18), pp. 184017-184040. https://doi.org/10.1088/0953-8984/20/18/184017

APA-Zitierstil: Assmann, J., Narkhede, V., Breuer, N., Muhler, M., Seitsonen, A., Knapp, M., Crihan, D., Farkas, A., Mellau, G., & Over, H. (2008). Heterogeneous oxidation catalysis on ruthenium: bridging the pressure and materials gaps and beyond. Journal of Physics: Condensed Matter. 20(18), 184017-184040. https://doi.org/10.1088/0953-8984/20/18/184017