Effect of a novel self-assembly based on coordination polymer with zinc porphyrin in supramolecular solar cells

Within this work, we firstly report the self-assemblies of zinc porphyrin coordination polymers (CPs) appended isonicotinic acid ligands by metal–ligand axial coordination approach immobilized on the nanostructured TiO₂ electrode surfaces in photoelectrochemical devices. Compared to the assemblies based on zinc porphyrins integrated isonicotinic acid ligands via metal–ligand axial coordination or metal–ligand edged binding approach, the CPs-based assemblies exhibit significantly improved photovoltaic performances. Especially, the assembly based on iminazole-substituted zinc porphyrin coordination polymer exhibits an excellent photovoltaic performance with a short circuit photocurrent density (J_sc) of 3.8 mA cm⁻², an open circuit voltage (V_oc) of 0.31 V, a fill factor (FF) of 0.67 and an overall conversion efficiency (η) of 0.48% under AM 1.5 conditions. The results serve as another good testing ground for the fabrication of supramolecular devices techniques in future.