1. Nano-Science Center, Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
2. Niels Bohr Institute, University of Copenhagen, Blegdamsvej 17, 2100 Copenhagen, Denmark
3. Materials Research Division, Risø National Laboratory for Sustainable Energy, Technical University of Denmark (DTU), Frederiksborgvej 399, Post Office Box 49, DK-4000 Roskilde, Denmark
4. Fuel Cell and Solid State Chemistry Division, Risø National Laboratory for Sustainable Energy, Technical University of Denmark (DTU), Frederiksborgvej 399, Post Office Box 49, DK-4000 Roskilde, Denmark