1. Department of Physical Chemistry, University of Innsbruck, Innrain 52c, A-6020 Innsbruck, Austria
2. Department of Heterogeneous Reactions, Max-Planck-Institute for Chemical Energy Conversion, Stiftstraße 34–36, 45470 Mülheim an der Ruhr, Germany
3. Department of Inorganic Chemistry, Fritz-Haber Institute of the Max-Planck Society, Faradayweg 4–6, 14195 Berlin, Germany
4. University Service Center for Transmission Electron Microscopy, TU Wien, Wiedner Hauptstraße 8–10, A-1040 Vienna, Austria