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Title: Properties of Pt-supported iron oxide ultra-thin films: Similarity of Hubbard-corrected and hybrid density functional theory description

We report a first principles study on the properties of Pt(111)-supported FeO(111) monolayer. We confront results issued from PBE+U and HSE06 approximations, and analyze the impact of the more accurate hybrid description of the electronic structure of the metal/oxide interface on a large variety of calculated characteristics of this system. In particular, we analyze the behavior of its work function and its consequences on the spontaneous charging of adsorbed Au adatoms. We also consider the FeO{sub 2} nano-oxide phase and its peculiar oxygen storage characteristics, responsible for the unusual catalytic properties of FeO{sub x}/Pt system. We show that while the hybrid approximation does indeed substantially improve the electronic characteristics of iron oxide, of individual Au adatoms, or oxygen molecules, its overall impact on the calculated properties of the composed FeO/Pt system is very small. We assign this to the relatively small effect of the hybrid approximation on the band structure alignment. This shows that the less computationally demanding DFT+U approximation remains a fully adequate tool in theoretical studies on this kind of systems. This is particularly important for calculations on realistic systems, with large-size reconstructions induced by the lattice mismatch at the interface between the two materials.
Authors:
; ;  [1] ; ;  [2] ;  [3]
  1. Dipartimento di Scienza dei Materiali, Universitá di Milano-Bicocca, via Cozzi, 55 - 20125 Milano (Italy)
  2. CNRS, UMR 7588, Institut des Nanosciences de Paris, F-75005 Paris (France)
  3. (France)
Publication Date:
OSTI Identifier:
22436588
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 141; Journal Issue: 14; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
77 NANOSCIENCE AND NANOTECHNOLOGY; APPROXIMATIONS; CRYSTAL DEFECTS; DENSITY FUNCTIONAL METHOD; ELECTRONIC STRUCTURE; INTERFACES; IRON OXIDES; MOLECULES; NANOSTRUCTURES; OXYGEN; THIN FILMS; WORK FUNCTIONS