1. Forschungszentrum Jülich GmbH; Institute of Energy and Climate Research - 5 Photovoltaics; 52425 Jülich Germany
2. Evonik Creavis GmbH; Paul-Baumann-Str. 1 45772 Marl Germany
3. Technical University Darmstadt; Institute of Material Science; Jovanka-Bontschits-Str. 2 64287 Darmstadt Germany