1. Research Center for New Energy Technology (RCNET), Shanghai Institute of Microsystem and Information Technology (SIMIT), Chinese Academy of Sciences (CAS), Jiading, 201800 Shanghai, People's Republic of China
2. University of Chinese Academy of Sciences (USAS), Shijingshan, 100049 Beijing, People's Republic of China
3. State Key Laboratory of PV Sciences and Technology (SKL-PVST), Trinasolar, Changzhou, 213031 Jiangsu, People's Republic of China