1. China-UK Low Carbon College, Shanghai Jiao Tong University, No. 3, Yinlian Road, Lingang, Shanghai 201306, People’s Republic of China
2. Laboratorium für Elektronenmikroskopie, Karlsruhe Institute of Technology (KIT), Engesserstraße 7, Karlsruhe D-76131, Germany
3. Department of Opto-Electronic Engineering, National Dong Hwa University, No. 1, Sec. 2, Da Hsueh Road, Shoufeng, Hualien 97401, Taiwan