Journalartikel

Jahr der Veröffentlichung: 2004

Seiten: 14634-14642

Zeitschrift: Journal of Physical Chemistry B (Soft Condensed Matter and Biophysical Chemistry)

Bandnummer: 108

Heftnummer: 38

ISSN: 1520-6106

DOI Link: https://doi.org/10.1021/jp0401675

Verlag: American Chemical Society

Abstract: 

The oxidation of CO over Ru/MgO and Ru/SiO₂ catalysts was
used as a simple model reaction to derive turnover frequencies at
atmospheric pressure, which were observed to agree with kinetic data
obtained under high-vacuum conditions with supported ruthenium catalysts
and the RuO₂(110) single-crystal surface. Thus, it was
possible to bridge both the pressure and the materials gap. However, a
partial deactivation was observed initially, which was identified as an
activated process, both under net reducing and net oxidizing conditions.
Temperature-programmed reduction (TPR) experiments were performed
subsequently in the same reactor, to monitor the degree of oxidation, as
a function of the reaction temperature and the CO/O₂
reactant feed ratio. Using in situ diffuse reflectance infrared Fourier
transform spectroscopy (DRIFTS) measurements, the structural changes of
the ruthenium catalysts during the oxidation of CO were confirmed, under
relevant reaction conditions. Under net reducing conditions, only
domains of RuO₂ seem to exist on the metallic ruthenium
particles, whereas, under net oxidizing conditions, the ruthenium
particles were fully oxidized to bulk RuO₂ particles, which may expose less-active facets, such as the RuO₂(100)−c(2 × 2) surface.

Harvard-Zitierstil: Assmann, J., Narkhede, V., Khodeir, L., Löffler, E., Hinrichsen, O., Birkner, A., et al. (2004) On the Nature of the Active State of Supported Ruthenium Catalysts Used for the Oxidation of Carbon Monoxide:  Steady-State and Transient Kinetics Combined with in Situ Infrared Spectroscopy, Journal of Physical Chemistry B (Soft Condensed Matter and Biophysical Chemistry), 108(38), pp. 14634-14642. https://doi.org/10.1021/jp0401675

APA-Zitierstil: Assmann, J., Narkhede, V., Khodeir, L., Löffler, E., Hinrichsen, O., Birkner, A., Over, H., & Muhler, M. (2004). On the Nature of the Active State of Supported Ruthenium Catalysts Used for the Oxidation of Carbon Monoxide:  Steady-State and Transient Kinetics Combined with in Situ Infrared Spectroscopy. Journal of Physical Chemistry B (Soft Condensed Matter and Biophysical Chemistry). 108(38), 14634-14642. https://doi.org/10.1021/jp0401675