Phosphorous tetrabenzocorrolazine from its metal-free phthalocyanine precursor: Its facile synthesis, high fluorescence emission, efficient singlet oxygen formation, and promising hole transporting material

Abstract

We have synthesized tetra(4-tert-butyl phenoxy)-tetrabenzocorrolazine phosphorous POTBC(β-OPB)4, a functional π-conjugated macrocycle compound derived from corrole or corrolazine, by a one step procedure from its metal free phthalocyanine precursor. The product structure is characterized by UV–Vis absorption, MS, NMR and IR spectral methods. We have also studied their fluorescence properties, excited triplet state formation, photosensitized singlet oxygen production, and their application as undoped hole transporting layer (HTL) in perovskite solar cells (PSC). The results show that POTBC(β-OPB)4 is highly emissive (fluorescence quantum yield 0.60 in the red region which is little affected by solvent), it also exhibits significant singlet oxygen formation ability (quantum yield 0.40 which is little influenced by solvent), and show remarkable power conversion efficiency (15.8%) as undoped HTL. These facts suggest that POTBC(β-OPB)4 is a promising fluorescence imaging agent and good singlet oxygen photosensitizer for photodynamic therapy of tumor. It is also a good candidate as undoped hole transporting material for PSC.