1. State Key Laboratory of Rare Earth Materials Chemistry and Applications
2. College of Chemistry and Molecular Engineering
3. Peking University
4. Beijing 100871
5. P. R. China
6. Beijing National Lab of Condensed Matter Physics
7. Institute of Physics
8. Chinese Academy of Sciences
9. Beijing 100190
10. CAS Key Laboratory of Materials for Energy Conversion and State Key Laboratory of High Performance Ceramics and Superfine Microstructure
11. Shanghai Institute of Ceramics
12. Shanghai 200050
13. Department of Materials Science and Engineering
14. University of Pennsylvania
15. Philadelphia
16. USA