[1] Huazhong Univ Sci & Technol, Wuhan Natl Lab Optoelect, Sch Opt & Elect Informat, Wuhan 430074, Hubei, Peoples R China
[2] Hong Kong Univ Sci & Technol, Dept Chem, Hong Kong, Hong Kong, Peoples R China
[3] Texas Tech Univ, Dept Chem & Biochem, Lubbock, TX 79409 USA