Berlin 2024 – wissenschaftliches Programm
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O: Fachverband Oberflächenphysik
O 49: Oxide and Insulator Interfaces I
O 49.9: Vortrag
Mittwoch, 20. März 2024, 12:30–12:45, MA 144
Dynamics of an Fe3O4(001) support for Ptn cluster catalysts under the fast STM — Sebastian Kaiser1, Johanna Reich2, Ueli Heiz1, Barbara A.J. Lechner2, and •Friedrich Esch1 — 1Chair of Physical Chemistry, TUM School of Natural Sciences and Catalysis Research Center, Technische Universität München, Lichtenbergstr. 4, 85748 Garching — 2Functional Nanomaterials Group, TUM School of Natural Sciences and Catalysis Research Center, Technische Universität München, Lichtenbergstr. 4, 85748 Garching
Reducible oxides are valuable supports for cluster catalysts in oxidation reactions due to their capability to contribute lattice oxygen. Here, we present a study on the surface dynamics of Fe3O4 in the absence and in the presence of supported size-selected Pt5 clusters [1, 2]. With our dedicated FAST add-on module [3], we drive our variable temperature scanning probe microscope at choice in a fast-imaging mode at movie rates of several images per second and in a particle-tracking mode that allows to follow diffusion paths with a time resolution down to 10 ms. This paves the way to unravel in situ a variety of surface dynamics at the atomic scale that remain hidden to static imaging: Hydrogen diffusion, subsurface Fe interstitial transport, hole growth upon catalytic surface reduction, and, finally, cluster diffusion in the Smoluchowski ripening regime, at the verge of encapsulation.
[1] S. Kaiser et al., ACS Catalysis 11, 9519 (2021).
[2] S. Kaiser et al., ACS Catalysis 13, 6203 (2023).
[3] C. Dri et al., Ultramicroscopy, 205, 49 (2019).
Keywords: Magnetite; Diffusion; Scanning tunneling microscopy; Platinum cluster; Oxidation catalysis