TY - JOUR
T1 - Over 16.7% efficiency of ternary organic photovoltaics by employing extra PC71BM as morphology regulator
AU - Gao, Jinhua
AU - Wang, Jian
AU - An, Qiaoshi
AU - Ma, Xiaoling
AU - Hu, Zhenghao
AU - Xu, Chunyu
AU - Zhang, Xiaoli
AU - Zhang, Fujun
N1 - Publisher Copyright:
© 2019, Science China Press and Springer-Verlag GmbH Germany, part of Springer Nature.
PY - 2020/1/1
Y1 - 2020/1/1
N2 - Ternary organic photovoltaics (OPVs) are fabricated with PBDB-T-2Cl:Y6 (1:1.2, wt/wt) as the host system and extra PC71BM as the third component. The PBDB-T-2Cl:Y6 based binary OPVs exhibit a power conversion efficiency (PCE) of 15.49% with a short circuit current (JSC) of 24.98 mA cm−2, an open circuit voltage (VOC) of 0.868 V and a fill factor (FF) of 71.42%. A 16.71% PCE is obtained in the optimized ternary OPVs with PBDB-T-2Cl:Y6:PC71BM (1:1.2:0.2, wt/wt) active layer, resulting from the synchronously improved JSC of 25.44 mA cm−2, FF of 75.66% and the constant VOC of 0.868 V. The incorporated PC71BM may prefer to mix with Y6 to finely adjust phase separation, domain size and molecular arrangement in ternary active layers, which can be confirmed from the characterization on morphology, 2D grazing incidence small and wide-angle X-ray scattering, as well as Raman mapping. In addition, PC71BM may prefer to mix with Y6 to form efficient electron transport channels, which should be conducive to charge transport and collection in the optimized ternary OPVs. This work provides more insight into the underlying reasons of the third component on performance improvement of ternary OPVs, indicating ternary strategy should be an efficient method to optimize active layers for synchronously improving photon harvesting, exciton dissociation and charge transport, while keeping the simple cell fabrication technology.
AB - Ternary organic photovoltaics (OPVs) are fabricated with PBDB-T-2Cl:Y6 (1:1.2, wt/wt) as the host system and extra PC71BM as the third component. The PBDB-T-2Cl:Y6 based binary OPVs exhibit a power conversion efficiency (PCE) of 15.49% with a short circuit current (JSC) of 24.98 mA cm−2, an open circuit voltage (VOC) of 0.868 V and a fill factor (FF) of 71.42%. A 16.71% PCE is obtained in the optimized ternary OPVs with PBDB-T-2Cl:Y6:PC71BM (1:1.2:0.2, wt/wt) active layer, resulting from the synchronously improved JSC of 25.44 mA cm−2, FF of 75.66% and the constant VOC of 0.868 V. The incorporated PC71BM may prefer to mix with Y6 to finely adjust phase separation, domain size and molecular arrangement in ternary active layers, which can be confirmed from the characterization on morphology, 2D grazing incidence small and wide-angle X-ray scattering, as well as Raman mapping. In addition, PC71BM may prefer to mix with Y6 to form efficient electron transport channels, which should be conducive to charge transport and collection in the optimized ternary OPVs. This work provides more insight into the underlying reasons of the third component on performance improvement of ternary OPVs, indicating ternary strategy should be an efficient method to optimize active layers for synchronously improving photon harvesting, exciton dissociation and charge transport, while keeping the simple cell fabrication technology.
KW - morphology regulator
KW - organic photovoltaics
KW - organic solar cells
KW - power conversion efficiency
KW - ternary strategy
UR - http://www.scopus.com/inward/record.url?scp=85075191718&partnerID=8YFLogxK
U2 - 10.1007/s11426-019-9634-5
DO - 10.1007/s11426-019-9634-5
M3 - Article
AN - SCOPUS:85075191718
SN - 1674-7291
VL - 63
SP - 83
EP - 91
JO - Science China Chemistry
JF - Science China Chemistry
IS - 1
ER -