Research Group Colsmann - Light Technology Institute (LTI)

Organic solar cells are an emerging technology that promises an economic use of commodities, a disposal without obligations and an unsurpassed energy payback time of only a few months, whereas silicon solar cells require more than one year to harvest back the energy consumed during fabrication. Organic solar cells will shape our future by combining research and technology development with perspectives for innovative applications and provisions for the world of tomorrow. In particular, organic solar cells open new pathways to the integration of photovoltaic modules into facades, windows or overhead glazing as well as many OEM products for automotive or consumer electronics. Plastic foil carriers enable mechanical flexibility of the modules and consequently their applicability to curved surfaces.

In order to push the limits of organic photovoltaic devices beyond the latest performance records, multi-disciplinary efforts by physicists, chemists, material scientists and engineers at the research group and its partners concentrate on finding new organic materials and device architectures for light harvesting. Tandem solar cells comprising two absorber layers for better light harvesting exhibit significantly enhanced power conversion efficiencies on laboratory scale. For a future production on larger scales, researchers work on fs-laser structured modules to reduce size dependent losses without losing cell area. Environmentally friendly non-halogenated solvents and organic nanoparticle dispersion in ethanol or water are evaluated for layer deposition to enable a transfer of lab based coating processes to industrial scale. Highly advanced thin-film deposition techniques in a cleanroom research environment and sophisticated nano-scale and large area characterization equipment in a photovoltaic exploration laboratory are available for fabrication and optimization of organic photovoltaic devices. Besides organic solar cells, related technologies like organic light-emitting diodes (OLEDs), as well as perovskite solar cells are investigated.