Low-gap zinc porphyrin as an efficient dopant for photomultiplication type photodetectors.

A new zinc porphyrin, named as Por4IC, was synthesized, which through extension of conjugation and an enhancement of planarity and donor–acceptor interactions exhibits a very low band gap. The molecule was able to efficiently facilitate a photomultiplication effect in blend with P3HT which was assisted by electron trapping followed by hole tunneling injection from the Al electrode giving rise to a high external quantum efficiency of 22 182% and a specific detectivity of 4.4 × 1012 Jones at 355 nm and at −15 V bias. This work introduces porphyrin derivatives as promising dopants for photomultiplication type photodetectors.