Regensburg 2022 – wissenschaftliches Programm
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O: Fachverband Oberflächenphysik
O 54: Poster Wednesday: 2D Materials 2
O 54.14: Poster
Mittwoch, 7. September 2022, 18:00–20:00, P4
Carbon Embedding of Pt Cluster Superlattices Templated by Hexagonal Boron Nitride on Ir(111) — •Tobias Hartl1, Moritz Will1, Pantelis Bampoulis1,2, Virginia Boix de la Cruz3, Paolo Lacovig4, Vedran Vonk5, Simon Chung5, Andreas Stierle5, Jan Knudsen3, Silvano Lizzit4, and Thomas Michely1 — 1Universität zu Köln — 2University of Twente — 3MAX IV Laboratory and Division of Synchrotron Radiation Research — 4Elettra-Sincrotrone Trieste S.C.p.A — 5DESY Hamburg
With the goal to delevop the fabrication of a new type of Pt-nanoparticle carbon support electrocatalyst, we investigate the carbon embedding of Pt cluster superlattices grown on the moiré of a monolayer of h-BN on Ir(111). Using STM and XPS we find that carbon embedding is conformal and does not deteriorate the excellent order of the clusters. The thermal and mechanical stability of the embedded clusters is greatly enhanced by the C forming a strong binding to the Pt clusters. Sintering as well as single cluster pick-up by the STM tip, are both suppressed. (Hartl, T. et al., J. Phys. Chem. C, 2021)
The only cluster decay path left takes place at an elevated temperature above 850 K. Cluster material penetrates through the h-BN sheet, whereby it becomes bound to the underlying metal. There are indications that while the a-C matrix and the Pt clusters bind strongly to each other, upon annealing both weaken their binding to h-BN.
We discuss how the binding between the membrane and the substrate can be weakened, such that it is possible to be split-off via a combination of hydrogen bubbling and dry transfer approaches.