1. Institut für Anorganische Chemie
2. Eberhard Karls Universität Tübingen
3. 72076 Tübingen
4. Germany
5. State Key Laboratory of Organic-Inorganic Composites
6. Beijing Key Laboratory of Electrochemical Process and Technology for Materials
7. Beijing University of Chemical Technology
8. Beijing 100029
9. P. R. China