1. Organic Electronics & Photovoltaics Group, Physical Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
2. Laboratoire de Physicochimie des Polymères et des Interfaces, Université de Cergy-Pontoise, 95000 Cergy, France
3. Cornell High Energy Synchrotron Source Cornell University, Ithaca, New York 14853, United States
4. Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695, United States