Binary solvent mixture boosting high efficiency of polymer solar cells

CB, CF and their mixture were selected as solvents to regulate molecular order and the nanoscale morphology of the photoactive layer. The casting solvents with different boiling points change the molecular organization time, therefore can optimize molecular ordering and phase separation. As a result, the efficiency of PBDB-T:INPIC-4F non-fullerene OSCs was improved from 8.1% to 13.1%.