a
Institute of Materials Research and Engineering (IMRE), Agency for Science, Technology and Research (A*STAR), 3 Research Link, Singapore 117602, Singapore
E-mail: chankl@imre.a-star.edu.sg
b
Solar and Alternative Energy Engineering Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia
E-mail: ghassan.jabbour@kaust.edu.sa
c
Microelectronics Research Center, University of Texas at Austin, Austin, USA
d
Center for Advanced Molecular Photovoltaics (CAMP), 476 Lomita Mall, Stanford University, Stanford, USA
E-mail: aselli@stanford.edu