Photo-physical processes in materials for photovoltaic applications based on conjugated polymers

Because of an increasing need for energy, exhaustion of conventional energy sources and pollution of the environment, the development of renewable energy supplies becomes increasingly important. Solar cells can play an important role to meet these demands, since they can directly convert solar light into electricity. Conventional solar cells have reached sufficiently high efficiencies for practical applications, however their high initial costs are a barrier for large-scale energy production. For this reason, organic solar cells are being developed for which cheap production methods are feasible, however, their efficiency still needs improvement. This thesis contributes to the realization of this improvement, since, by means of research on the photoactive materials applied in these solar cells, insight is provided in the relation between the composition and the nano-morphology of these materials and the production, the transport and the decay of charge carriers after excitation in the visible. The knowledge obtained can be used to identify bottlenecks in the operation of organic solar cells and to determine for different types of organic solar cells which nano-morphology should be pursued. If methods can be developed to produce solar cells with this ideal nano-morphology, higher efficiencies can be expected.Applied Science