Regensburg 2019 – scientific programme

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O: Fachverband Oberflächenphysik

O 75: Fundamentals of Catalysis I

O 75.5: Talk

Thursday, April 4, 2019, 11:45–12:00, H5

Modelling Ostwald ripening beyond mean-field models — •Elisabeth M. Dietze and Philipp N. Plessow — Institute of Catalysis Research and Technology (IKFT), Karlsruhe Institute of Technology, Karlsruhe, Germany

Transport of atoms and molecules via the gas-phase plays an important role in many processes in heterogeneous catalysis. One of the challenges for heterogeneous catalysts in industry is deactivation due to sintering. For example, platinum particles are widely used in exhaust gas after treatment, but suffer from sintering trough ripening by volatile PtO₂ under oxidizing conditions.

We have recently proposed a kinetic Monte Carlo (kMC) model for the explicit simulation of gas-phase mass transport.[1] On small length scales that correspond to typical distances between nanoparticles, transport in model systems was found to deviate significantly from Fick’s laws. We are currently exploring, how that affects sintering, when compared with mean-field models suggested in the literature. [2-3]

References: [1] Dietze, E. M.; Plessow, P. N., J. Phys. Chem. C 2018, 122 (21), 11524-11531. [2] Campbell, C. T.; Mao, Z., ACS Catal. 2017, 7 (12), 8460-8466. [3] Plessow, P. N.; Abild-Pedersen, F., ACS Catal. 2016, 6 (10), 7098-7108.