[1] Peking Univ, Sch Mat Sci & Engn, Beijing 100871, Peoples R China
[2] Chinese Acad Sci, Changchun Inst Appl Chem, State Key Lab Electroanalyt Chem, Changchun 130022, Peoples R China
[3] Harbin Engn Univ, Coll Mat Sci & Chem Engn, Minist Educ, Key Lab Superlight Mat & Surface Technol, Harbin 150001, Peoples R China
[4] Chinese Acad Sci, Inst Phys, Beijing Natl Lab Condensed Matter Phys, Beijing 100190, Peoples R China