Berlin 2015 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
O: Fachverband Oberflächenphysik
O 6: Catalysis
O 6.7: Talk
Monday, March 16, 2015, 12:15–12:30, MA 043
A perturbative approach for quantifying mass transfer limitations in in-situ model catalyst studies — •Sebastian Matera1,2, Sara Blomberg3, Max J. Hoffmann1, Johan Zetterberg3, Johan Gustafson3, Edvin Lundgren3, and Karsten Reuter1,4 — 1Technische Universität München, Germany — 2Freie Universität Berlin, Germany — 3Lund University, Sweden — 4Stanford University, USA
Reaction chambers in in-situ studies of defined model catalysts often prohibit the disentangling of surface chemistry and gas phase transport by idealized reactor models. A full Computational Fluid Dynamics (CFD) treatment, however, is computationally extremely costly due to the stiff surface kinetics requiring very small times steps. We present a perturbative approach which decomposes the problem, such that the CFD can be performed with a low reactivity, non-stiff surface chemistry. The actual solution to the targeted problem, is then approximated in a post processing phase. In order to analyze recent Planar Laser Induced Fluorescence experiments [2] on the CO oxidation at Pd(100), we combine the perturbative approach with our first-principles based multi-scale modelling methodology integrating kinetic Monte Carlo simulations into CFD [1]. We find that a mixture of two different surface terminations explains the experiment the best, where the observed the reactivity stems from the minority termination. [1] S. Matera, M. Maestri, A. Cuoci, and K. Reuter, ACS Catal. 4, 4081 (2014). [2] J. Zetterberg et al., Rev. Sci. Instrum. 83, 053104 (2012)