Regensburg 2019 – wissenschaftliches Programm

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

O: Fachverband Oberflächenphysik

O 49: Metal Substrates III: Structure, Epitaxy and Growth

O 49.5: Vortrag

Mittwoch, 3. April 2019, 11:30–11:45, H5

Formation of PtRu surface alloy on Ru(0001) substrate: A kinetic Monte Carlo study — •David Mahlberg and Axel Groß — Institut für Theoretische Chemie, Universität Ulm, 89069 Ulm, Deutschland

Optimising the reactivity and selectivity of a specific catalytic reaction by the rational design of heterogeneous catalysts requires a comprehensive understanding of the factors underlying their reactivity and stability. A precise control of surface properties then allows to improve the performance of catalysts. In particular bimetallic surfaces offer the possibility to tailor their catalytic properties by deliberately modifying their composition and/or structural arrangement, which depends on the mixing ratio of the two metal elements.

We have studied the stability of PtRu/Ru(0001) surface alloys by kinetic Monte Carlo simulation using first-principles electronic structure calculations in order to derive the barriers for vacancy diffusion. Thus the structure formation of surface alloys on macroscopic time scales and mesoscopic length scales as a function of composition and temperature can be monitored for varying Pt concentrations. We will analyse the dependence of the diffusion barriers on the particular arrangement of the surface alloy based on the interaction between the constituents.