[1] Zhengzhou Univ, Sch Mat Sci & Engn, Zhengzhou 450001, Henan, Peoples R China
[2] Univ Bath, Dept Chemtsiry, Bath BA2 7AY, Avon, England
[3] Zhengzhou Univ Aeronaut, Sch Mat Sci & Engn, Henan Key Lab Aeronaut Mat & Applicat Technol, Zhengzhou 450046, Henan, Peoples R China
[4] Peking Univ, Sch Phys, Electron Microscopy Lab, Beijing 100871, Peoples R China
[5] Peking Univ, Sch Phys, Int Ctr Quantum Mat, Beijing 100871, Peoples R China
[6] Zhengzhou Univ, Henan Prov Supercomp Ctr, Zhengzhou 450001, Henan, Peoples R China