1. Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Nanoscale Materials Science, Überlandstrasse 129, 8600 Dübendorf, Switzerland
2. Organic Chemistry Institute, University of Zurich, Winterthurerstrasse 190, 8057 Zürich, Switzerland
3. Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Campus UAB, 08193 Bellaterra, Spain