Photosensitization of asymmetric molecular, and bimolecular aliphatic-μ-bridged-meso-phenyl porphyrin

Abstract

The desired asymmetric metal-free porphyrin derivatives were prepared by condensing freshly prepared the phenyl dipyrraomethane and triphenyl tetrapyrrane building blocks with the different molar ratios of acetaldehyde ([Formula: see text]CHO), and glutaraldehyde (OHC([Formula: see text]CHO, Glu). The obtained asymmetric [3+1] ([Formula: see text]Por, [Formula: see text]Por-[Formula: see text]-([Formula: see text]Por) and [2+2] ([Formula: see text]Por, [Formula: see text]-([Formula: see text] oligomer) porphyrin derivatives were characterized by UV-Vis, FT-IR, and 1H NMR. Their photoelectric properties were investigated by examining their current density-voltage (J-V) curves in dark, and under artificial sunlight, illumination using standard bulk heterojunction cell arrangements. The [Formula: see text]-V plots show that they display photosensitive semiconducting properties in the range of ([Formula: see text] = 1.7–14.5 [Formula: see text]S/cm) with negligible photovoltaic effects. All data were compared to those of symmetric metal-free [Formula: see text]Por([Formula: see text] = 33.8 [Formula: see text]S/cm). Density functional theory (DFT) is employed to validate the ground-state molecular geometry.