NW: Charge separation at nanostructured molecular donor-acceptor interfaces

Organic donor and acceptor molecules represent an important class of materials for solar energy conversion. The focus of this project is to combine the complementary expertise of four groups to address central issues for photovoltaic cells based on these materials. These are: film structure and morphology, electronic structure at interfaces, excitonic processes and charge transport. The goal of this concerted approach is to develop a detailed understanding of the correlation between structural and electronic properties both in the film and at interfaces, microscopic transport phenomena and macroscopic parameters determining solar cell performance for different prototypes of donor/acceptor pairs. This knowledge should enable growing films with favourable properties for exciton and charge transport in both the donor and acceptor phase and efficient charge separation and extraction at the involved interfaces. Starting from a simple planar heterojunction we will proceed to more complex structures, including interdigitated organic/organic interfaces and bulk-heterojunctions to achieve this goal.