[Zurück]

M. Ulreich, Z. Jakub, F. Kraushofer, M. Meier, M. Schmid, U. Diebold, C. Franchini, G. Parkinson:
"Atomic-Scale Studies of Hydroformylation on Rh1/Fe₃O₄(001)";
Poster: DPG-Frühjahrstagung (DPG Spring Meeting) of the Surface Science Division, SurfaceScience21, virtual; 04.03.2021.

Hydroformylation (alkene + CO + H2 → aldehyde) is an important industrial reaction typically performed in solution using highly-selective mononuclear complexes. Recently, Rh-based "single-atom" catalysts (SACs) have been shown to catalyze this reaction heterogeneously with similar levels of selectivity, suggesting SAC can be a strategy to heterogenize problematic reactions. The main advantage of heterogeneous catalysis is easy separation of the catalyst from the products. SAC is intended to unify this advantage with the high selectivity and activity of homogeneous catalysis. In this talk, TPD and XPS are used to study the coadsorption of ethylene and carbon monoxide on isolated Rh1 adatoms on Fe3O4(001), a critical first step in the hydroformylation reaction. Our results show that 2-fold coordinated Rh1 adatoms on Fe3O4(001) are able to coadsorb C2H4 and CO, but 5-fold coordinated Rh1 adatoms cannot. We conclude that gaining control of the active site geometry is key to the development of highly-selective single-atom catalysis.