SurfaceScience21 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
O: Fachverband Oberflächenphysik
O 88: Poster Session VII: Oxides and insulators: Adsorption and reaction of small molecules I
O 88.4: Poster
Donnerstag, 4. März 2021, 10:30–12:30, P
Comparison of single Rh adatoms on α-Fe2O3(1102) and TiO2(110) stabilized by adsorbed water — •Lena Haager1, Florian Kraushofer1, Moritz Eder2, Ali Rafsanjani-Abbasi1, Giada Franceschi1, Michele Riva1, Panukorn Sombut1, Marlene Atzmueller1, Michael Schmid1, Cesare Franchini3,4, Ulrike Diebold1, and Gareth S. Parkinson1 — 1Institute of Applied Physics, TU Wien, Vienna, Austria — 2Chair of Physical Chemistry, TU München, Germany — 3University of Vienna, Vienna, Austria — 4Universitá di Bologna, Bologna, Italy
Despite its high cost, rhodium is a widely applied catalyst primarily used in nanoparticle form for converting toxic gases in automobiles. It is also utilized in organometallic complexes, such as the Wilkinson catalyst, for the hydrogenation of olefins and for converting alkenes to aldehydes through a process known as hydroformylation. So-called single-atom catalysis offers an opportunity to reduce the amount of Rh required for traditional heterogeneous catalysis, and a path to heterogenize homogeneous reactions, with the advantage of easy separation of catalyst and product.
Using STM, nc-AFM and XPS we compare the stability of Rh adatoms on two different model supports: α-Fe2O3(1102) and TiO2(110), both in UHV and 2*10−8 mbar of water. We show that the Rh adatoms on α-Fe2O3(1102) sinter in UHV, but are stabilized by water up to 150 ∘C through coordination to 2–3 OH ligands. In contrast, Rh adatoms on TiO2(110) could not be stabilized above room temperature in either environment.