Digging Its Own Site

Author(s)
Ali Rafsanjani-Abbasi, Florian Buchner, Faith J. Lewis, Lena Puntscher, Florian Kraushofer, Panukorn Sombut, Moritz Eder, Jiří Pavelec, Erik Rheinfrank, Giada Franceschi, Viktor Birschitzky, Michele Riva, Cesare Franchini, Michael Schmid, Ulrike Diebold, Matthias Meier, Georg K.H. Madsen, Gareth S. Parkinson
Abstract

Determining the local coordination of the active site is a prerequisite for the reliable modeling of single-atom catalysts (SACs). Obtaining such information is difficult on powder-based systems and much emphasis is placed on density functional theory computations based on idealized low-index surfaces of the support. In this work, we investigate how Pt atoms bind to the (11̅02) facet of α-Fe2O3; a common support material in SACs. Using a combination of scanning tunneling microscopy, X-ray photoelectron spectroscopy, and an extensive computational evolutionary search, we find that Pt atoms significantly reconfigure the support lattice to facilitate a pseudolinear coordination to surface oxygen atoms. Despite breaking three surface Fe-O bonds, this geometry is favored by 0.84 eV over the best configuration involving an unperturbed support. We suggest that the linear O-Pt-O configuration is common in reactive Pt-based SAC systems because it balances thermal stability with the ability to adsorb reactants from the gas phase. Moreover, we conclude that extensive structural searches are necessary to determine realistic active site geometries in single-atom catalysis.

Organisation(s)
Computational Materials Physics
External organisation(s)
Technische Universität Wien, University of Bologna
Journal
ACS Nano
Volume
18
Pages
26920-26927
No. of pages
8
ISSN
1936-0851
DOI
https://doi.org/10.1021/acsnano.4c08781
Publication date
10-2024
Peer reviewed
Yes
Austrian Fields of Science 2012
103018 Materials physics
Keywords
ASJC Scopus subject areas
General Materials Science, General Engineering, General Physics and Astronomy
Portal url
https://ucrisportal.univie.ac.at/en/publications/b71bf6cd-07d7-429d-91eb-2bc055b544f4