1. Department of Chemistry and Applied Biosciences ETH Zurich Vladimir Prelog Weg 1 Zurich CH‐8093 Switzerland
2. Laboratory for Transport at Nanoscale Interfaces Swiss Federal Laboratories for Materials Science and Technology Überlandstrasse 129 Dübendorf CH‐8600 Switzerland
3. Department of Mechanical and Process Engineering ETH Zurich Sonneggstrasse 3 Zurich CH‐8092 Switzerland
4. Laboratory for Thin Films and Photovoltaics Swiss Federal Laboratories for Materials Science and Technology Überlandstrasse 129 Dübendorf CH‐8600 Switzerland
5. Department of Physics University of Basel Klingelbergstrasse 82 Basel CH‐4056 Switzerland