@article{475a4b20f5bc450fb22a798c7a666888,
title = "Charge carrier dynamics in PffBT4T-2OD: PCBM organic solar cells",
abstract = "We investigate the charge carrier dynamics of inverted organic solar cells (OSCs) based on PffBT4T-2OD: PCBM and PTB7: PCBM – the two leading systems among the OSCs based on polymer-fullerene bulk-heterojunction – to elucidate the origin of their performance difference. Transient absorption spectroscopy (TAS) and photo-electrochemical impedance spectroscopy (photo-EIS) were employed to unravel the photo-physics that govern the cell operation of these two highly efficient bulk heterojunction OSCs. While photo-EIS indicates that the two systems under study exhibit similar behavior in terms of recombination, TAS results reveal that PffBT4T-2OD: PCBM systems not only have higher charge generation rate but also more efficient charge transfer than PTB7: PCBM systems, leading to the power conversion efficiency of PffBT4T-2OD: PCBM-based OSCs (9.16\%) that is higher than that of PTB7: PCBM-based OSCs (6.44\%).",
keywords = "Electrochemical impedance spectroscopy, Organic solar cells, PCBM, PCBM, PffBT4T-2OD, PTB7, Transient absorption spectroscopy",
author = "Ramakant Sharma and Vinay Gupta and Hyunwoo Lee and Kunal Borse and Ram Datt and Chhavi Sharma and Mahesh Kumar and Seunghyup Yoo and Dipti Gupta",
note = "Funding Information: The authors would like to acknowledge Solar Energy Research Initiative (SERI) program (Grant No. DST/TM/SERI/2k12/21(G) DTD03/07/2013 ), Indo-UK (APEX) program (Phase II), EEWS-2014-N01140 052 from Climate Change Research Hub Project of the KAIST EEWS Research Center (EEWS: Energy, Environment, Water and Sustainability) and Indo Korea Research Internship (IKRI) program (Order No. INT/ROK/IKRI-15/2014 ) of Department of Science and Technology (DST), India. This work was supported by the New \& Renewable Energy Core Technology Program of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) granted financial resource from the Ministry of Trade, Industry and Energy (MOTIE) of the Republic of Korea (No. 20163010012200 ). The authors also thank National Nanofabrication Center at Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Korea for providing various facilities for device characterization. RD thanks the UGC for the Junior Research Fellowship. Publisher Copyright: {\textcopyright} 2018 Elsevier B.V.",
year = "2018",
month = nov,
doi = "10.1016/j.orgel.2018.08.018",
language = "British English",
volume = "62",
pages = "441--447",
journal = "Organic Electronics",
issn = "1566-1199",
publisher = "Elsevier B.V.",
}
