TY - JOUR
T1 - 17.1% Efficient Single-Junction Organic Solar Cells Enabled by n-Type Doping of the Bulk-Heterojunction
AU - Lin, Yuanbao
AU - Firdaus, Yuliar
AU - Nugraha, Mohamad Insan
AU - Liu, Feng
AU - Karuthedath, Safakath
AU - Emwas, Abdul-Hamid M.
AU - Zhang, Weimin
AU - Seitkhan, Akmaral
AU - Neophytou, Marios
AU - Faber, Hendrik
AU - Yengel, Emre
AU - McCulloch, Iain
AU - Tsetseris, Leonidas
AU - Laquai, Frédéric
AU - Anthopoulos, Thomas D.
N1 - KAUST Repository Item: Exported on 2020-10-01
Acknowledged KAUST grant number(s): OSR-2018-CARF/CCF-3079
Acknowledgements: This publication is based upon work supported by the King Abdullah University of Science and Technology (KAUST) Office of Sponsored Research (OSR) under Award No: OSR-2018-CARF/CCF-3079. L.T. acknowledges support for the computational time granted from the GRNET facility ARIS under project STEM-2.
PY - 2020/2/13
Y1 - 2020/2/13
N2 - Molecular doping is often used in organic semiconductors to tune their (opto) electronic properties. Despite its versatility, however, its application in organic photovoltaics (OPVs) remains limited and restricted to p-type dopants. In an effort to control the charge transport within the bulk-heterojunction (BHJ) of OPVs, the n-type dopant benzyl viologen (BV) is incorporated in a BHJ composed of the donor polymer PM6 and the small-molecule acceptor IT-4F. The power conversion efficiency (PCE) of the cells is found to increase from 13.2% to 14.4% upon addition of 0.004 wt% BV. Analysis of the photoactive materials and devices reveals that BV acts simultaneously as n-type dopant and microstructure modifier for the BHJ. Under optimal BV concentrations, these synergistic effects result in balanced hole and electron mobilities, higher absorption coefficients and increased charge-carrier density within the BHJ, while significantly extending the cells’ shelf-lifetime. The n-type doping strategy is applied to five additional BHJ systems, for which similarly remarkable performance improvements are obtained. OPVs of particular interest are based on the ternary PM6:Y6:PC71BM:BV(0.004 wt%) blend for which a maximum PCE of 17.1%, is obtained. The effectiveness of the n-doping strategy highlights electron transport in NFA-based OPVs as being a key issue.
AB - Molecular doping is often used in organic semiconductors to tune their (opto) electronic properties. Despite its versatility, however, its application in organic photovoltaics (OPVs) remains limited and restricted to p-type dopants. In an effort to control the charge transport within the bulk-heterojunction (BHJ) of OPVs, the n-type dopant benzyl viologen (BV) is incorporated in a BHJ composed of the donor polymer PM6 and the small-molecule acceptor IT-4F. The power conversion efficiency (PCE) of the cells is found to increase from 13.2% to 14.4% upon addition of 0.004 wt% BV. Analysis of the photoactive materials and devices reveals that BV acts simultaneously as n-type dopant and microstructure modifier for the BHJ. Under optimal BV concentrations, these synergistic effects result in balanced hole and electron mobilities, higher absorption coefficients and increased charge-carrier density within the BHJ, while significantly extending the cells’ shelf-lifetime. The n-type doping strategy is applied to five additional BHJ systems, for which similarly remarkable performance improvements are obtained. OPVs of particular interest are based on the ternary PM6:Y6:PC71BM:BV(0.004 wt%) blend for which a maximum PCE of 17.1%, is obtained. The effectiveness of the n-doping strategy highlights electron transport in NFA-based OPVs as being a key issue.
UR - http://hdl.handle.net/10754/661532
UR - https://onlinelibrary.wiley.com/doi/abs/10.1002/advs.201903419
UR - http://www.scopus.com/inward/record.url?scp=85079365241&partnerID=8YFLogxK
U2 - 10.1002/advs.201903419
DO - 10.1002/advs.201903419
M3 - Article
C2 - 32274320
SN - 2198-3844
SP - 1903419
JO - Advanced Science
JF - Advanced Science
ER -