BTP-4F-12 (CAS number 2389125-23-7), also known as Y12, is a family member of BTP-4F (Y6). The two materials are very similar with the only difference between Y12 and Y6 being that Y12 has two butyloctyl side chains to the [1,2,5]thiadiazolo[3,4-e]thieno[2",3’':4’,5']thieno[2',3':4,5]pyrrolo[3,2-g]thieno[2',3':4,5]thieno[3,2-b]indole core while Y6 bears two ethylhexyl chains.
Comparing to Y6, Y12 has greater solubility and for this reason, Y12 has great advantage for solution processability and mass device production with environmentally benign solvents as active layer materials for organic polymer solar cells.
While PM6 (PBDB-T-2F) was used as the low band-gap donor polymer, mixed two well-compatible non-fullerene acceptors BTP-4F-12 and MeIC showed a great device performance with 17.4% efficiency and a high open-circuit voltage of 0.863 with minimum energy loss.
Device structure: ITO/PEDOT:PSS/PM6:BTP-4F-12:MeIC/PDIN/Al. [1]