Coupled Organic-Inorganic Nanostructures: From Tailored Electronic Properties to Carrier-Selective Transport and Optoelectronic Devices

• Applicants: Professor Dr. Wolfgang Brütting; Professor Dr. Marcus Scheele; Professor Dr. Frank Schreiber
• Subject Area: Physical Chemistry of Solids and Surfaces, Material Characterisation
• Term: from 2016 to 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 282208125

The outstanding physical properties of shape- and size-controlled nanoparticles are already being exploited for commercially available technologies: HD-televisions with unprecedented color depth on the basis of CdSe nanoparticles, printable lead sulfide quantum dot solar cells with power conversion efficiencies > 8 % and flexible transistors made from chalcogenidometalate-functionalized nanoparticles are only a few examples. Essentially, all of the above mentioned technological advances were realized due to a deepened understanding of the electronic coupling between adjacent nanoparticles and the tailored manipulation of the nanoparticles ligand sphere. Upon applying short-chained molecules to functionalize the nanoparticles surfaces, the mean particle-particle distance is drastically reduced which improves the electric functionality of ensembles of such nanoparticles and the performance of the devices in which they are applied. However, this strategy often requires hazardous substances like hydrazine which restricts large-scaleapplications. Moreover, the prospects of further improvements are limited as the most developed protocols in pursue of this conceptalready apply mono-atomic ligands, such that even shorted particleparticle distances are unlikely. Our project addresses this issue and provides a different approach to coupled nanoparticle solids: We apply organic semiconductor molecules which bear an importantadvantage over the short ligand strategy: Due to their distinct electronic structure, these molecules themselves are conductive suchthat they can provide a channel for electric transport between adjacent nanoparticles. By functionalizing the nanoparticles surfaceswith such molecules, we seek to explore the prospects of this novel strategy in the fabrication of optoelectronic devices

• DFG Programme: Research Grants