title: Employing X-ray Photoelectron Spectroscopy for Determining Layer Homogeneity in Mixed Polar Self-Assembled Monolayers.
abstract: Self-assembled monolayers (SAMs) containing embedded dipolar groups offer the particular advantage of changing the electronic properties of a surface without affecting the SAM-ambient interface. Here we show that such systems can also be used for continuously tuning metal work functions by growing mixed monolayers consisting of molecules with different orientations of the embedded dipolar groups. To avoid injection hot-spots when using the SAM-modified electrodes in devices, a homogeneous mixing of the two components is crucial. We show that a combination of high-resolution X-ray photoelectron spectroscopy with state-of-the-art simulations is an ideal tool for probing the electrostatic homogeneity of the layers and thus for determining phase separation processes in polar adsorbate assemblies down to inhomogeneities at the molecular level.
authors.affiliation: Institute of Solid State Physics, NAWI Graz, Graz University of Technology , Petersgasse 16, 8010 Graz, Austria.
authors.forename: Iris
authors.initials: I
authors.lastname: Hehn
authors.affiliation: Angewandte Physikalische Chemie, Universität Heidelberg , Im Neuenheimer Feld 253, 69120 Heidelberg, Germany.
authors.forename: Swen
authors.initials: S
authors.lastname: Schuster
authors.affiliation: Angewandte Physikalische Chemie, Universität Heidelberg , Im Neuenheimer Feld 253, 69120 Heidelberg, Germany.
authors.forename: Tobias
authors.initials: T
authors.lastname: Wächter
authors.affiliation: Institut für Anorganische und Analytische Chemie, Universität Frankfurt , Max-von-Laue-Straße 7, 60438 Frankfurt, Germany.
authors.forename: Tarek
authors.initials: T
authors.lastname: Abu-Husein
authors.affiliation: Institut für Anorganische und Analytische Chemie, Universität Frankfurt , Max-von-Laue-Straße 7, 60438 Frankfurt, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Terfort
authors.affiliation: Angewandte Physikalische Chemie, Universität Heidelberg , Im Neuenheimer Feld 253, 69120 Heidelberg, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Zharnikov
authors.affiliation: Institute of Solid State Physics, NAWI Graz, Graz University of Technology , Petersgasse 16, 8010 Graz, Austria.
authors.forename: Egbert
authors.initials: E
authors.lastname: Zojer