[Zhang, Yong-Gang; Ma, Li-Li; Yu, Kewang Ying; Li, Jia-Lin; Yu, Ying; Tan, Ming] Huazhong Normal Univ, Coll Phys Sci & Technol, Wuhan 430079, Peoples R China.
[Sun, Hai-Zhen] Xiamen Univ, Dept Chem, Coll Chem & Chem Engn, Xiamen 361005, Peoples R China.
[Lin, Yu-Lin] Xiamen Tungsten Co Ltd, Wuhan 361004, Peoples R China.
[Wang, Jian-Bo] Wuhan Univ, Ctr Electron Microscopy, Wuhan 430072, Peoples R China.