1. Institute of Physics; Technische Universität Ilmenau; 98693 Ilmenau Germany
2. Laboratory of Organic and Macromolecular Chemistry (IOMC); Friedrich Schiller University Jena; Humboldtstrasse 10 07743 Jena Germany
3. Center for Energy and Environmental Chemistry Jena (CEEC Jena); Friedrich Schiller University Jena; Philosphenweg 7a 07743 Jena Germany
4. Department of Physics and Astronomy; Vrije Universiteit Amsterdam; 1081 Amsterdam The Netherlands
5. CHOSE, Department of Electronic Engineering; University of Rome “Tor Vergata”; 00133 Rome Italy
6. Catalan Institute of Nanoscience and Nanotechnology (ICN2); Nanostructured Materials for Photovoltaic Energy Group; Building ICN2, Campus UAB E-08193 Bellaterra (Barcelona) Spain
7. Consejo Superior de Investigaciones Científicas (CSIC); Building ICN2, Campus UAB E-08193 Bellaterra (Barcelona) Spain