1. State Key Laboratory of Material Processing and Die & Mould Technology School of Materials Science and Engineering Huazhong University of Science and Technology Wuhan 430074 P. R. China
2. Solar Energy Research Institute of Singapore National University of Singapore Singapore 117574 Singapore
3. School of Materials Science and Engineering Nanyang Technological University Singapore 639798 Singapore
4. State Key Laboratory of Modern Optical Instrumentation College of Information Science and Electronic Engineering Zhejiang University Hangzhou 310027 P. R. China
5. Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Organic Solids Beijing 100190 P. R. China
6. Singapore‐HUJ Alliance for Research and Enterprise (SHARE) Campus for Research Excellence and Technological Enterprise (CREATE) Singapore 138602 Singapore
7. Sino‐Singapore International Joint Research Institute (SSIJRI) Guangzhou 510000 P. R. China