TY - JOUR
T1 - Negligible Energy Loss during Charge Generation in Small-Molecule/Fullerene Bulk-Heterojunction Solar Cells Leads to Open-Circuit Voltage over 1.10 v
AU - Babics, Maxime
AU - Duan, Tainan
AU - Balawi, Ahmed H.
AU - Liang, Ru Ze
AU - Cruciani, Federico
AU - Carja, Ionela Daniela
AU - Gottlieb, Dale
AU - McCulloch, Iain
AU - Vandewal, Koen
AU - Laquai, Frédéric
AU - Beaujuge, Pierre M.
N1 - Funding Information:
This publication is based upon work supported by the King Abdullah University of Science and Technology (KAUST) Office of Sponsored Research (OSR) under Award CRG-R2-13-BEAU-KAUST-1. The authors acknowledge concurrent support under Baseline Research Funding from KAUST. T.D. acknowledges financial support from National Natural Science Foundation of China (21702202).
Funding Information:
This publication is based upon work supported by the King Abdullah University of Science and Technology (KAUST) Office of Sponsored Research (OSR) under Award CRG_R2_13_BEAU_KAUST_1. The authors acknowledge concurrent support under Baseline Research Funding from KAUST. T.D. acknowledges financial support from National Natural Science Foundation of China (21702202).
Publisher Copyright:
© 2019 American Chemical Society.
PY - 2019/4/22
Y1 - 2019/4/22
N2 - Solution-processable small molecules (SMs) that can serve as donors in bulk-heterojunction (BHJ) solar cells are practical alternatives to their polymer counterparts. However, SM-fullerene blends commonly suffer severe voltage losses. In general, devices that reach open-circuit voltages (VOC) > 1 V yield low photocurrents in BHJ solar cells with fullerene acceptors (e.g., PC71BM) and modest power conversion efficiencies (PCEs). In this contribution, we report on the design, synthesis, and BHJ device characteristics of a new SM donor, 2F-DRCN5T, yielding a VOC of up to 1.10 V with PC71BM as the fullerene acceptor, while maintaining PCEs > 7% (over 8% achieved upon solvent-vapor-annealing (SVA) treatment). The negligible energy loss during charge generation (ΔECT), the deep-lying HOMO of 2F-DRCN5T inferred from its large ionization potential (IP), the high charge-transfer-state energy (ECT) of the blend, and a reduced nonradiative voltage loss account for the high VOC achieved in BHJ solar cells.
AB - Solution-processable small molecules (SMs) that can serve as donors in bulk-heterojunction (BHJ) solar cells are practical alternatives to their polymer counterparts. However, SM-fullerene blends commonly suffer severe voltage losses. In general, devices that reach open-circuit voltages (VOC) > 1 V yield low photocurrents in BHJ solar cells with fullerene acceptors (e.g., PC71BM) and modest power conversion efficiencies (PCEs). In this contribution, we report on the design, synthesis, and BHJ device characteristics of a new SM donor, 2F-DRCN5T, yielding a VOC of up to 1.10 V with PC71BM as the fullerene acceptor, while maintaining PCEs > 7% (over 8% achieved upon solvent-vapor-annealing (SVA) treatment). The negligible energy loss during charge generation (ΔECT), the deep-lying HOMO of 2F-DRCN5T inferred from its large ionization potential (IP), the high charge-transfer-state energy (ECT) of the blend, and a reduced nonradiative voltage loss account for the high VOC achieved in BHJ solar cells.
KW - fluorination
KW - high open-circuit voltage
KW - low energy loss
KW - oligothiophene
KW - organic photovoltaics
KW - small-molecule donor
UR - http://www.scopus.com/inward/record.url?scp=85064843360&partnerID=8YFLogxK
U2 - 10.1021/acsaem.8b02020
DO - 10.1021/acsaem.8b02020
M3 - Article
AN - SCOPUS:85064843360
SN - 2574-0962
VL - 2
SP - 2717
EP - 2722
JO - ACS Applied Energy Materials
JF - ACS Applied Energy Materials
IS - 4
ER -