Photophysical properties of new bis-perylene dyads for potential upconversion use

Two new bis-perylenes, BPC with a meta-disubstituted benzene linker, and BPD with a p,p′-disubstituted biphenyl linker, have been synthesized and their photophysical parameters measured. Their singlet and triplet energies decrease incrementally in the order perylene, BPC, BPD, making them ideally matched with C60 for triplet–triplet energy transfer in sensitized photon upconversion schemes. Following photosensitization by triplet C60, BPC exhibits strong fluorescence upconversion by triplet–triplet annihilation, indicating that these bis-perylene dyads (and the multimers that can be constructed from them) will be interesting candidates for use in organic devices such as bulk-heterojunction and dye-sensitized solar cells employing non-coherent photon upconversion.