1. Department of Materials and Environmental Chemistry, Stockholm University, 106 91 Stockholm, Sweden
2. Wallenberg Wood Science Center, Department of Materials and Environmental Chemistry, Stockholm University, 10691 Stockholm, Sweden
3. Department of Chemistry, Philipps-Universität Marburg, 35032 Marburg, Germany
4. Institute of Inorganic Chemistry, Leibniz University Hannover, D-30167 Hannover, Germany
5. Ångström Solar Center, Division of Solar Cell Technology, Uppsala University, 751 21 Uppsala, Sweden
6. Laboratory of Organic Electronics, Department of Science and Technology (ITN), Linköping University, SE-60174 Norrköping, Sweden