Oxidation induced restructuring of Rh-Ga SCALMS model catalyst systems
Wittkämper H, Maisel S, Wu M, Frisch J, Wilks RG, Grabau M, Spiecker E, Bär M, Görling A, Steinrück HP, Papp C (2020)
Publication Type: Journal article
Publication year: 2020
Journal
Book Volume: 153
Pages Range: 104702-
Journal Issue: 10
DOI: 10.1063/5.0021647
Abstract
Supported catalytically active liquid metal solutions have been receiving increasing attention recently. We investigated the oxidation behavior of macroscopic Rh-Ga alloy droplets and Rh-Ga model catalyst nanoparticles supported on SiO2/Si(100) with low Rh content (<2.5 at. %) by x-ray photoelectron spectroscopy in ultra-high vacuum and under near-ambient pressure conditions using different photon energies and also using transmission electron microscopy. The experiments are accompanied by computational studies on the Ga oxide/Rh-Ga interface and Rh-Ga intermetallic compounds. For both Rh-Ga alloy droplets and Rh-Ga model catalyst nanoparticles, exposure to molecular oxygen leads to the formation of an oxide shell in which Rh is enriched. Transmission electron microscopy on the Rh-Ga nanoparticles confirms the formation of an ∼4 nm thick gallium oxide film containing Rh. Based on ab initio molecular dynamics and computational studies on the Ga2O3/Ga interface, it is concluded that Rh incorporation into the Ga2O3 film occurs by substituting octahedrally coordinated Ga.
Authors with CRIS profile
Haiko Wittkämper
Lehrstuhl für Physikalische Chemie II
Sven Maisel
Lehrstuhl für Theoretische Chemie
Mingjian Wu
Lehrstuhl für Werkstoffwissenschaften (Mikro- und Nanostrukturforschung)
Mathias Grabau
Lehrstuhl für Physikalische Chemie II
Erdmann Spiecker
Lehrstuhl für Werkstoffwissenschaften (Mikro- und Nanostrukturforschung)
Marcus Bär
Professur für Röntgenspektroskopie (HIERN)
Andreas Görling
Lehrstuhl für Theoretische Chemie
Hans-Peter Steinrück
Lehrstuhl für Physikalische Chemie II
Christian Papp
Lehrstuhl für Physikalische Chemie II
Additional Organisation(s)
Lehrstuhl für Werkstoffwissenschaften (Mikro- und Nanostrukturforschung)
Interdisziplinäres Zentrum, Center for Nanoanalysis and Electron Microscopy (CENEM)
Involved external institutions
Germany (DE)How to cite
APA:
Wittkämper, H., Maisel, S., Wu, M., Frisch, J., Wilks, R.G., Grabau, M.,... Papp, C. (2020). Oxidation induced restructuring of Rh-Ga SCALMS model catalyst systems. Journal of Chemical Physics, 153(10), 104702-. https://doi.org/10.1063/5.0021647
MLA:
Wittkämper, Haiko, et al. "Oxidation induced restructuring of Rh-Ga SCALMS model catalyst systems." Journal of Chemical Physics 153.10 (2020): 104702-.
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