cm5b04570_si_001.pdf (1.93 MB)
Electron Acceptors Based on α‑Substituted Perylene Diimide (PDI) for Organic Solar Cells
journal contribution
posted on 2016-01-20, 00:00 authored by Donglin Zhao, Qinghe Wu, Zhengxu Cai, Tianyue Zheng, Wei Chen, Jessica Lu, Luping YuPerylene
diimide (PDI) derivatives functionalized at the ortho-position
(αPPID, αPBDT) were synthesized and used as electron acceptors
in non-fullerene organic photovoltaic cells. Because of the good planarity
and strong π-stacking of ortho-functionalized PDI, the αPPID
and αPBDT exhibit a strong tendency to form aggregates, which
endow the materials with high electron mobility. The inverted OPVs employing αPDI-based compounds as the acceptors
and PBT7-Th as the donor give the highest power conversion efficiency
(PCE) values: 4.92% for αPBDT-based devices and 3.61% for αPPID-based
devices, which are, respectively, 39% and 4% higher than that of their
β-substituted counterparts βPBDT and βPPID. Charge
separation studies show more efficient exciton dissociation at interfaces
between αPDI-based compounds and PTB7-Th. The results suggest
that α-substituted PDI derivatives are more promising electron
acceptors for organic photovoltaic (OPV) components than β-isomers.