1. Institut für Physik, Martin-Luther-Universität Halle-Wittenberg, 06120 Halle, Germany
2. ALBA Synchrotron Light Source, Cerdanyola del Vallès, 08290 Barcelona, Spain
3. Department of Energy Conversion and Storage, Technical University of Denmark, DK-2800 Kgs Lyngby, Denmark
4. Department of Chemical Engineering and Materials Science, University of Minnesota-Twin Cities, Minneapolis, Minnesota 55455, USA
5. Department of Engineering and Computer Sciences, Hamburg University of Applied Sciences, 20099 Hamburg, Germany
6. Max-Planck-Institut für Mikrostrukturphysik, 06120 Halle, Germany
7. Institute of Theoretical Physics, Johannes Kepler University, 4040 Linz, Austria
8. Laboratory for Nanoelectronic Devices, Swiss Federal Institute of Technology-EPFL, 1015 Lausanne, Switzerland