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

O: Fachverband Oberflächenphysik

O 88: Gerhard Ertl Young Investigator Award

O 88.1: Hauptvortrag

Donnerstag, 15. März 2018, 10:30–11:00, MA 005

Syngas reactions on metal surfaces studied using scaling-relation-based kinetic Monte Carlo — •Mie Andersen — Theoretical Chemistry, Technische Universität München, Germany

The complexity of catalytic reactions on surfaces calls for efficient means of estimating adsorption energies and reaction barriers, which are required input for a microkinetic model. One commonly used approach is to employ scaling relations [1], which are linear relations between the adsorption energies of atomic and molecular species on various (typically metal) surfaces, in combination with simple rate equations for the catalytic activity based on the mean-field approximation (MFA). In my talk, I will demonstrate the prospects of instead combining scaling relations with kinetic Monte Carlo simulations, which allow for predicting the catalytic activity while taking into account spatial correlations in the distribution of the adsorbates on the surface. For the specific case of methane synthesis from syngas on stepped metal surfaces, I demonstrate that MFA models may overestimate the catalytic activity of metal catalysts by several orders of magnitude due to the neglect of spatial correlations [2]. Finally, I will discuss recent and ongoing work aimed at (i) overcoming challenges related to a large disparity in the timescales of the surface processes, (ii) accounting for lateral interactions between the adsorbates, and (iii) dealing with more complex reaction networks such as the synthesis of higher alcohols on metal catalysts.

[1] F. Abild-Pedersen, Catal. Today 272, 6 (2016)

[2] M. Andersen et al., J. Chem. Phys. 147, 152705 (2017)