[1] Guangxi Univ, Ctr Nanoenergy Res, Sch Phys Sci & Technol, Nanning 530004, Guangxi, Peoples R China
[2] Chinese Acad Sci, CAS Ctr Excellence Nanosci, Beijing Inst Nanoenergy & Nanosyst, Beijing Key Lab Micronano Energy & Sensor, Beijing 101400, Peoples R China
[3] Univ Chinese Acad Sci, Sch Nanosci & Technol, Beijing 100049, Peoples R China
[4] Guangxi Univ, Res Ctr Optoelect Mat & Devices, Sch Phys Sci & Technol, Nanning 530004, Peoples R China