New Type Of Azoles/Ferrocene Group Substituted Porphyrin Axial Coordinate Self-Assembly In Dye-Sensitized Solar Cells

Dye-sensitized solar cells?DSSCs? based on mesoporous nanocrystalline oxides are a promising low-cost alternative to conventional silicon-based solar cells for the conversion of solar energy to electric power. Because of the critical role of sensitizers in DSSC performance, optimizing molecular design is essential to maximize power conversion efficiency?h?. Current high-efficiency DSSCs?h=10–12%? have been based on Ru complexes as sensitizers. However, the limited supply and potential environmental impact of Ru have led to intensive search for newfashioned, green, organic-based dyes. Porphyrins are a family of organic dyes that are fascinating for application in DSSCs owing to their extremely high molar extinction coefficients and synthetic versatility. A drawback of typical porphyrins is poor light-harvesting property at wavelengths around 450 nm and > 600 nm. Indeed, with elongation of ?-conjugation as well as enhancement of push–pull character in porphyrins, the absorption can be shifted and broadened, making it possible to increase the light-harvesting property and the resultant ?-value. Based on above studies, this paper designed and synthesized several metalloporphyrins containing different substituents, and then using single anchoring porphyrins or double-layer porphyrins axial coordination pattern assembled on mesoporous nanocrystalline TiO₂ films. We conducted an experimental comparison about the effect of different different monocase anchoring or bilayer porphyrin supramolecular self-assemblies on the spectral, electrochemical and photovoltaic performances of the DSSCs. The specific work is as follows:1. Two new "Trans-A₂B₂" types of zinc porphyrins based on meso-two substituted with tetrazole or imidazolyl group have been successfully synthesized and characterized, while immobilized on the nanostructured TiO₂ electrode surfaces and researched photoelectric property of the DSSCs devices. In addition, the performance of these devices will be further studied by the UV-visible absorption spectras, Density functional theory and TEM analyses.2. Several "Trans-A₂BC" types of anchoring metalloporphyrins based on meso-substituted with tetrazole or imidazole group have been successfully synthesized and characterized, while anchored to the nanostructured TiO₂ semiconductor surfaces by-COOH group, then a zinc porphyrin was bound to the anchoring porphyrin using zinc-to-ligand axial coordination approach, researched photoelectric property of the DSSCs devices. In addition, the performance of these devices will be further studied by the UV-visible absorption spectras, Density functional theory, TEM analyses and Electrochemical impedance spectroscopy?EIS? spectra.3. Three new "Trans-A₂B₂" types of zinc porphyrins based on meso-two substituted with ferrocene group have been successfully synthesized and characterized. Immobilized on the nanostructured TiO₂ electrode surfaces used axial coordination approach, another zinc porphyrin was introduced as anchoring porphyrin. In addition, the photoelectric property and UV-visible absorption spectras of the DSSCs devices were researched.