[1] Tsinghua Univ, Dept Chem, Beijing 100084, Peoples R China
[2] Chinese Acad Sci, Inst Chem, Ctr Mol Sci, Beijing 100080, Peoples R China
[3] Natl Ctr Nanosci & Technol, Beijing 100080, Peoples R China
[4] Jilin Univ, Dept Chem, Changchun 130023, Peoples R China