1. Department of Inorganic
Solid State Chemistry, University of Rostock, Albert-Einstein-Strasse 3a, D-18059 Rostock, Germany
2. Shanghai Institute of Ceramics, Chinece Academy of Sciences, Shanghai 200050, P. R. China
3. School of Materials Science and Engineering, Shanghai University, No. 99 Shangda Road, Shanghai 200072, P. R. China