COIN

Gekoppelte organisch-anorganische Nanostrukturen: Von maßgeschneiderten elektronischen Eigenschaften über selektiven Ladungstransport zu optoelektronischen Bauteilen

05/02/2016 to 04/02/2019

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-scale applications. Moreover, the prospects of further improvements are limited as the most developed protocols in pursue of this concept already apply mono-atomic ligands, such that even shorted particle-particle 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 important advantage over the “short ligand strategy”: Due to their distinct electronic structure, these molecules themselves are conductive such that they can provide a channel for electric transport between adjacent nanoparticles. By functionalizing the nanoparticles’ surfaces with such molecules, we seek to explore the prospects of this novel strategy in the fabrication of optoelectronic devices.