Epitaxial Cobalt Oxide Films with Wurtzite Structure on Au(111)

Ammon MM, Baumann S, Kißlinger T, Rieger J, Fauster T, Redinger J, Hammer L, Schneider MA (2021)

Publication Type: Journal article

Publication year: 2021

Journal

Physica Status Solidi-Rapid Research Letters Wiley-VCH Verlag

DOI: 10.1002/pssr.202100383

Abstract

Several-nanometer-thick, closed, and epitaxial cobalt(II) oxide films with wurtzite crystal structure (w-CoO) are grown on Au(111) and their structural and electronic properties analyzed. The structural quality of the (Formula presented.) oriented, oxygen-terminated, and unreconstructed films allow the application of surface-science methods to unravel the properties of this unusual polymorph of CoO and may pave the way for future thin-film applications. An experimental structural analysis by low-energy electron diffraction (LEED-IV) is presented with an excellent agreement between measured and calculated intensity spectra expressed by a Pendry R-factor of (Formula presented.) and few-picometer error bounds in the parameter values. Using scanning tunneling spectroscopy (STS) the bandgap of the semiconducting films is found to be 1.4 ± 0.2 eV. Ultraviolet photoelectron spectroscopy (UPS) confirms the presence of a gap and the position of the Fermi level (E F). The structural results of density functional theory calculations using (hybrid) functionals to treat electron correlations and van der Waals forces agree well with the experimentally determined structure of the antiferromagnetic w-CoO films. In contrast to generalized gradient approximation (GGA)+U calculations, the Heyd–Scuseria–Ernzerhof hybrid functional reproduces the semiconducting nature correctly and predicts surface states in the gap which might pin E F in agreement with STS and UPS.

Authors with CRIS profile

Maximilian Michael Ammon Lehrstuhl für Festkörperphysik Sara Baumann Lehrstuhl für Festkörperphysik Tilman Kißlinger Lehrstuhl für Festkörperphysik Janek Rieger Lehrstuhl für Festkörperphysik Thomas Fauster Lehrstuhl für Festkörperphysik Lutz Hammer Lehrstuhl für Festkörperphysik Alexander Schneider Professur für Experimentalphysik

Related research project(s)

Spectroscopy and Electronic Structure (funCOS) FOR 1878: funCOS - Funktionale molekulare Strukturen auf komplexen Oxidoberflächen Aug. 1, 2013 - Dec. 31, 2020 Local Atomic and Electronic Structure (funCOS) FOR 1878: funCOS - Funktionale molekulare Strukturen auf komplexen Oxidoberflächen Aug. 1, 2013 - July 31, 2019

Involved external institutions

Technische Universität Wien / Vienna University of Technology AT Austria (AT)

How to cite

APA:

Ammon, M.M., Baumann, S., Kißlinger, T., Rieger, J., Fauster, T., Redinger, J.,... Schneider, M.A. (2021). Epitaxial Cobalt Oxide Films with Wurtzite Structure on Au(111). Physica Status Solidi-Rapid Research Letters. https://dx.doi.org/10.1002/pssr.202100383

MLA:

Ammon, Maximilian Michael, et al. "Epitaxial Cobalt Oxide Films with Wurtzite Structure on Au(111)." Physica Status Solidi-Rapid Research Letters (2021).

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