Single-Molecule Spectroscopy on Polythiophene Conjugated Polymers and Aggregates: Towards Structure - Function Relationships

• Applicant: Professor Dr. Richard Hildner
• Subject Area: Physical Chemistry of Molecules, Liquids and Interfaces, Biophysical Chemistry ; Experimental Condensed Matter Physics
• Term: from 2012 to 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 230137142

Polythiophene p-conjugated polymers are a very popular class of organic functional materials and are exploited in novel optoelectronic devices, such as photovoltaic cells and field-effect transistors. Despite the successful applications of this conjugated polymer its electronic structure is still not fully understood. In particular the character of the electronically excited states is subject to discussion. In this project we will employ complementary single-molecule techniques, i.e. fluorescence and fluorescence excitation spectroscopy as well as time-resolved spectroscopy, to study the photophysical properties of individual polythiophene chains as a function of their length, their local environment, their conformation, and the temperature. This will allow to unravel clear correlations between the electronic and geometric properties of this technologically highly relevant material class. Finally, we will also investigate the photophysics of single polythiophene aggregates, that play an important role for the performance of organic devices. Here the aim will be to reveal the subtle interplay between intra- and inter-chain interactions that is key to understand (charge and energy) transport processes within and between such aggregates.

• DFG Programme: Research Grants