Dresden 2017 – wissenschaftliches Programm
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O: Fachverband Oberflächenphysik
O 61: Heterogeneous Catalysis
O 61.5: Poster
Dienstag, 21. März 2017, 18:30–20:30, P2-OG2
Ethylene hydrogenation on supported Ni, Pd and Pt nanoparticles: Catalyst activity, deactivation and the d-band model — Andrew S. Crampton1, Marian D. Rötzer1, •Maximilian Krause1, Florian F. Schweinberger1, Bokwon Yoon2, Uzi Landman2, and Ueli Heiz1 — 1Technische Universität München, Lehrstuhl für Physikalische Chemie, Zentralinstitut für Katalyseforschung und Fakultät für Chemie, Lichtenbergstr. 4, 85748 Garching, Germany — 2School of Physics, Georgia Institute of Technology, Atlanta, GA 30332-0430, USA
Ethylene was hydrogenated over cluster-ensembles with narrow size distributions. Ni, Pd and Pt particles (1-1.5 nm) were softlanded on an MgO(100)-thin film on Mo(100) (Xn/MgO(100)/Mo(100); X=Ni, Pd, Pt). The pulsed molecular beam reactive scattering (p-MBRS) technique was employed at 300 and 400 K to test the catalytic activity and deactivation of the particles.
While Pt particles showed the highest hydrogenation activity, they were also the most stable particles upon heating to 400 K. A trend within the group of the periodic table was found: Pd particles were less stable and active than Pt, Ni particles the least.
єc, the position of the d-band centroid taken from density functional theory calculations, correlates with the trend in activity and stability: for Pt єc lies the farthest away from the Fermi edge, for Ni the nearest.
For further characterization the particles were adsorbed with CO before and after reaction and examined with infrared reflection absorption spectroscopy.