CO-Induced Dimer Decay Responsible for Gem-Dicarbonyl Formation on a Model Single-Atom Catalyst

Author(s)
Chunlei Wang, Panukorn Sombut, Lena Puntscher, Zdenek Jakub, Matthias Meier, Jiri Pavelec, Roland Bliem, Michael Schmid, Ulrike Diebold, Cesare Franchini, Gareth S. Parkinson
Abstract

The ability to coordinate multiple reactants at the same active site is important for the wide-spread applicability of single-atom catalysis. Model catalysts are ideal to investigate the link between active site geometry and reactant binding, because the structure of single-crystal surfaces can be precisely determined, the adsorbates imaged by scanning tunneling microscopy (STM), and direct comparisons made to density functional theory. In this study, we follow the evolution of Rh1 adatoms and minority Rh2 dimers on Fe3O4(001) during exposure to CO using time-lapse STM at room temperature. CO adsorption at Rh1 sites results exclusively in stable Rh1CO monocarbonyls, because the Rh atom adapts its coordination to create a stable pseudo-square planar environment. Rh1(CO)2 gem-dicarbonyl species are also observed, but these form exclusively through the breakup of Rh2 dimers via an unstable Rh2(CO)3 intermediate. Overall, our results illustrate how minority species invisible to area-averaging spectra can play an important role in catalytic systems, and show that the decomposition of dimers or small clusters can be an avenue to produce reactive, metastable configurations in single-atom catalysis.

Organisation(s)
Computational Materials Physics
External organisation(s)
Technische Universität Wien, Brno University of Technology, Advanced Research Center for Nanolithography (ARCNL), University of Bologna
Journal
Angewandte Chemie - International Edition
Volume
63
No. of pages
9
ISSN
1433-7851
DOI
https://doi.org/10.1002/anie.202317347
Publication date
01-2024
Peer reviewed
Yes
Austrian Fields of Science 2012
104008 Catalysis
Keywords
ASJC Scopus subject areas
Catalysis, Chemistry(all)
Portal url
https://ucrisportal.univie.ac.at/en/publications/coinduced-dimer-decay-responsible-for-gemdicarbonyl-formation-on-a-model-singleatom-catalyst(bb4b119f-6b32-4e21-9a87-eb30e38b19b4).html