Performance enhancement of BODIPY dimer-based small-molecule solar cells using a visible-photon-capturing diketopyrrolopyrrole π-bridge

We report herein that the use of a diketopyrrolopyrrole instead of a 4,8-dithienyl benzodithiophene π-bridge makes a BODIPY dimer become capable of capturing and exploiting visible solar photons via intramolecular energy transfer, and affording a crystalline blend film with PC71BM, and consequently, a 7.3% absorption enhancement leads to a 70% increase in the photocurrent and efficiency.