1. Institute for Material Science and Center for Nanointegration Duisburg-Essen (CENIDE)
2. University of Duisburg-Essen
3. Essen 45141, Germany
4. Center for Nanophase Materials Sciences
5. Oak Ridge National Laboratory
6. Oak Ridge, USA
7. Institute of Materials Science
8. Technische Universität Darmstadt
9. Darmstadt 64287, Germany