1. Organic Semiconductor Research CenterChongqing Institute of Green and Intelligent TechnologyChongqing School, University of Chinese Academy of Sciences (UCAS Chongqing)Chinese Academy of Sciences Chongqing 400714 P. R. China
2. University of Chinese Academy of Sciences Beijing 100049 P. R. China
3. School of Materials Science and EngineeringLanzhou Jiaotong University Lanzhou 730070 P. R. China
4. College of Chemistry and Chemical EngineeringGuangxi University for Nationalities Nanning 530006 China
5. Department of Energy & Materials EngineeringDongguk University Seoul 04620 South Korea
6. Pohang Accelerator LaboratoryPohang University of Science and Technology Pohang 37673 Korea
7. Center for Nano Science and Technology@PolimiIstituto Italiano di Tecnologia Milan 20133 Italy
8. KAUST Solar CenterKing Abdullah University of Science and Technology Thuwal 23955-6900 Saudi Arabia
9. Department of Chemistry and Centre for Plastic ElectronicsImperial College London London SW7 2AZ UK