Influence of fluorination on the properties and performance of isoindigo-quaterthiophene-based polymers

Here a series of isoindigo (ID) and quaterthiophene (T4)-based donor-acceptor copolymers are synthesized and compared. The polymer with fluorination on the donor unit exhibits the strongest extent of temperature-dependent aggregation, which leads to a higher hole mobility of the polymer and PSCs with efficiencies up to 7.0% without using any processing additives. Our results provide important insights into how fluorination affects the aggregation properties and performance of isoindigo-based polymers.