1. IEK-5 Photovoltaics, Forschungszentrum Jülich GmbH, Wilhelm-Johnen Straße, 52425 Jülich, Germany
2. Faculty of Electrical Engineering and Information Technology, RWTH Aachen University, 7 Mies-van-der-Rohe-Straße 15, 52074 Aachen, Germany
3. Faculty of Engineering and CENIDE, University of Duisburg-Essen, Carl-Benz-Str. 199, 47057 Duisburg, Germany
4. Institute of Inorganic Chemistry, University of Cologne, Greinstr. 6, 50939 Cologne, Germany
5. IBI-3 Institute of Biological Information Processing, Forschungszentrum Jülich GmbH, Wilhelm-Johnen Straße, 52425 Jülich, Germany