1. Condensed Matter and Interfaces, Debye Institute for Nanomaterials Science, Utrecht University, Post Office Box 80000, 3508 TA Utrecht, The Netherlands
2. Laboratory of Inorganic Materials Chemistry, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, Postbox 513, 5600 MB Eindhoven, The Netherlands
3. EMAT, Department of Physics, University of Antwerpen, Groenenborgerlaan 171, 2010 Antwerpen, Belgium
4. Electron Microscopy Utrecht, Debye Institute for Nanomaterials Science, Utrecht University, 3584 CH Utrecht, Netherlands