[Guo, Rongshuo; Zhang, Xinyi; Zhang, Ye; Jin, Linghua; Zhang, Y] Univ South China, Sch Chem & Chem Engn, Lab Optoelect Technol Low Dimens Nanomat, Hengyang 421001, Peoples R China.
[Chen, Yinxiang] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.
[Zhang, Xinyi; Zhang, Ye; Peng, Guowen; Zhang, Y] Univ South China, Sch Resources Environm & Safety Engn, Hengyang 421001, Peoples R China.
[Chen, Yinxiang] Univ South China, Sch Comp Sci & Technol, Hengyang 421001, Peoples R China.
[Hans, Agren; Kuklin, Artem] Uppsala Univ, Dept Phys & Astron, Box 516, SE-75120 Uppsala, Sweden.