Project Details
Projekt
Local Atomic and Electronic Structure
Subject Area
Physical Chemistry of Solids and Surfaces, Material Characterisation
Inorganic Molecular Chemistry - Synthesis and Characterisation
Experimental Condensed Matter Physics
Solid State and Surface Chemistry, Material Synthesis
Physical Chemistry of Molecules, Liquids and Interfaces, Biophysical Chemistry
Inorganic Molecular Chemistry - Synthesis and Characterisation
Experimental Condensed Matter Physics
Solid State and Surface Chemistry, Material Synthesis
Physical Chemistry of Molecules, Liquids and Interfaces, Biophysical Chemistry
Term
from 2013 to 2022
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 214951840
The project funCOS 1 aims at investigating molecular adsorption, self-assembly and covalent network formation on oxide surfaces at the atomic scale. For that it employs low-temperature Scanning Tunneling Microscopy and non-contact Atomic Force Microscopy in ultra-high vacuum.Molecules from the funCOS molecular toolbox will be deposited on CoO, Co3O4, and MgO surfaces and their adsorption behavior and self-assembly will be studied at the atomic scale. FunCOS 1 will further develop the steering of molecular self-assembly by the choice of molecular side-groups and by activating intermolecular binding schemes that are not yet investigated on oxides. The hydrogen bonding between carboxyl and amino groups, halogen bonding and the formation metal-coordinated networks on oxide surfaces is of prime interest. The thermal stability of the functional groups and metal adatoms on oxides will be investigated.Related to the activation of functional groups are other modifications of the molecule-substrate interaction introduced by on-surface reactions of the molecules. A prominent example is the self-self-metalation of free-base porphyrins found on MgO and CoO during the first funCOS funding period. There are hints that hydrogen released during self-metalation might induce structural changes on CoO influencing molecular adsorption and self-assembly. This project will therefore study in detail the properties of hydrogen and hydroxyls on cobalt oxide and magnesium oxide surfaces. This will be achieved by intentionally supplying hydrogen atoms or hydroxyls by an atom source or by the dissociation of water respectively. Further, dehydrogenative or dehalogenated homocoupling between molecules, and the formation of covalent networks employing metalorganic bonds will be studied on oxide surfaces. The potential of functionalizing oxide surfaces will be explored by investigating the role of atomic-scale defects, naturally occurring or created by ion or electron irradiation, in triggering or even catalyzing appropriate surface reactions. Finally, scanning probe spectroscopies will be used to determine the electronic properties of the molecular systems. By Scanning Tunneling Spectroscopy molecular frontier orbitals and the energy-level alignment at the molecule-oxide interface will be studied. By Kelvin Probe Force Microscopy local contact potential differences within molecular layers and across the molecule-oxide interface will be investigated.The activities of this project are well embedded within the activities of the funCOS research unit. The local view complements the studies of molecular adsorption by non-local electron spectroscopy and scattering methods employed in the other funCOS projects. In collaboration with funCOS 6 a theoretical modeling of the scanning probe results will be devised.
DFG Programme
Research Units
