[1] Guangxi Univ, Ctr Nanoenergy Res, Sch Phys Sci & Technol, Nanning 530004, Guangxi, Peoples R China
[2] Chinese Acad Sci, Beijing Inst Nanoenergy & Nanosyst, CAS Ctr Excellence Nanosci, Beijing Key Lab Micronano Energy & Sensor, Beijing 101400, Peoples R China
[3] Univ Chinese Acad Sci, Sch Nanosci & Engn, Beijing 100049, Peoples R China
[4] Kunming Univ Sci & Technol, Coll Mat Sci & Engn, Kunming 650093, Peoples R China