Coupled Organic-Inorganic Nanostructures

We combine semiconductor and/or plasmonic nanocrystals with organic pi-systems into coupled organic-inorganic nanostructures (COIN). COINs can be understood as conductive metal organic frameworks, in which the metal centers are replaced by semiconductor or plasmonic nanocrystals. This uniquely allows to exploit quantum effects, such as the quantum size effect, to tune the properties of the material with minimal alterations in their chemical composition. COINs are conductive, exhibit a large degree of long-range structural order/orientation and a high density of organic/inorganic interfaces on the nanoscale. Our research focusses on utilizing the unique properties of COINs on several levels:

1) Self-assembly on liquid surfaces allows us to synthesize modular COIN thin films with a large variety of inorganic and organic constituents.

2) We study the fundamentals of transport in COINs as p-type, n-type or ambipolar transistors.

3) The combination of long-range order and electronic coupling allows us to investigate structure-transport correlations in synthetic mesocrystalline systems.

4) Charge- and energy transfer across the organic/inorganic interface is exploited by us for highly efficient photonic upconversion.

5) The large sensitivity towards light and the unique photophysical behaviour of excitons at the organic/inorganic interface leads to novel optical switches with sensitive and fast conversion of optical into electrical data as, for instance, in optical transceivers.

6) The various chemical functionalities in COINs and the large sensitivity towards structural changes are studied for applications as Chemiresistors for organic vapor sensing.