Berlin 2018 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

O: Fachverband Oberflächenphysik

O 23: Focus Session: Molecular Nanostructures on surfaces - New Concepts towards Complex Architectures II

O 23.5: Vortrag

Dienstag, 13. März 2018, 11:45–12:00, MA 004

Two-dimensional band structure in honeycomb metal-organic frameworks on epitaxial graphene — •Peter Liljeroth — Department of Applied Physics, Aalto University, Helsinki, Finland

Metal-organic frameworks (MOFs) are an important class of materials that present intriguing opportunities in, e.g., the fields of sensing, gas storage, catalysis, and optoelectronics. While there is a tremendous number of examples of three-dimensional, bulk, MOFs, synthesis strategies for two-dimensional (2D), monolayer thick MOFs are more limited. These systems are drawing growing interest as a promising platform for realizing designer materials with engineered electronic structures. The synthesis of 2D-MOFs is usually carried out on metal surfaces (e.g. Au, Ag, Cu), where it is difficult to access their intrinsic electronic properties.

We demonstrate synthesis of cobalt-dicyanobiphenyl and cobalt-dicyanoanthracene MOFs on epitaxial graphene and characterize their atomic geometry and electronic structure using atomic force microscopy (AFM), scanning tunneling microscopy and spectroscopy (STM and STS). We show the formation of a strongly coupled 2D electronic system in a MOF synthesized on a weakly interacting substrate. These results open the experimental path towards stand-alone MOF-based designer optoelectronic materials with complex, engineered electronic structures. The direct growth of 2D MOFs on graphene outlines possibilities of heterostructures with inorganic 2D materials with potential applications in sensors, catalysis and optoelectronics.