Tri-diketopyrrolopyrrole molecular donor materials for high-performance solution-processed bulk heterojunction solar cells

Two new high-performance DPP-containing donor molecules employing a molecular architecture with three DPP chromorphores (tri-DPP) in conjugated backbones are synthesized and characterized. The two tri-DPP molecules with only a structural difference on alkyl substitutions, when blended with PC71 BM, lead to power conversion efficiencies up to 4.8 and 5.5%, respectively.