Regensburg 2013 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

O: Fachverband Oberflächenphysik

O 20: Surface Chemical Reactions and Heterogeneous Catalysis II

O 20.6: Vortrag

Montag, 11. März 2013, 17:15–17:30, H33

Mass transfer effects during near-ambient CO oxidation at Pd(100) in non-ideal reactor chambers — •Sebastian Matera, Max J. Hoffmann, and Karsten Reuter — TU München

A central goal in in-situ studies of defined model catalysts has been to obtain (at best) as resolved spectro- or microscopic information as has been established in UHV surface science. With this focus possible heat and mass transport limitations in the ambient environments have not received much attention. In parts they are even unavoidable, considering the often significant constraints that in-situ techniques impose on the design of the reactor chamber. We investigate such effects with our newly developed first-principles based multi-scale modeling approach integrating kinetic Monte Carlo simulations into a fluid dynamical treatment [1]. Apart from the conceptual discussion in idealized reactor geometries [2], it is in particular the recent integration of our scheme into the general purpose CatalyticFOAM solver [3] that now enables us to also explicitly address the complex flow profiles in actual in-situ reactor chambers. We demonstrate the crucial role of heat and mass transfer limitations, in particular for the unselective and therefore high turnover CO oxidation in the context of recent in-situ XPS and Planar Laser Induced Fluorescence (PLIF) measurements over Pd(100) [4]. [1] S. Matera and K. Reuter, Catal. Lett. 133, 156 (2009). [2] S. Matera and K. Reuter, Phys. Rev. B 82, 085446 (2010); J. Catal. 295,261 (2012). [3] M. Maestri and A. Cuoci, CatalyticFOAM, www.catalyticfoam.polimi.it [4] S. Blomberg, J. Gustafson, E. Lundgren et al., in preparation.