1. Research Center
of Nano Science and Technology, Shanghai University, Shanghai, Shanghai 200444, P. R. China
2. Department
of Chemistry and Biochemistry, University of California, Santa Cruz, California 95064, United States
3. State Key Laboratory of Rare Earth Resource
Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, P. R. China