Preparation And Photoelectric Properties Of New Porphyrin Derivatives

Porphyrin compounds are a kind of macrocyclic conjugated organic molecules which have an extensive system of delocalizedπelectrons. They can be applied in many fields, such as electron transfer, energy conversion, photocatalytic materials and nonlinear optical materials. As a result, functionalized modification of porphyrin unit has received more and more interest in recent years. Main research results in this paper were summarized as follows:1. Five D-A porphyrin molecules have been synthesized through the conjugated ring of porphyrin was replaced with different conjugate structure. Their electrochemical and spectroscopic properties were studied. The results showed that there are interactions between donor and accepter in five D-A porphyrin molecules. Because of different substituting groups, there are different change rules in the ultraviolet absorbs and redox potential in compounds. The intramolecular partial charge transfer was confirmed by the theoretical calculation.2. p-MWNTs-TiO2 and p-MWNTs/ZnTPP-TiO2 composite photocatalysts were prepared by sol-gel method. The physical properties of the composites were characterized by thermogravimetric analysis(TGA),transmission electron microscope(TEM), X-ray powder diffraction(XRD) and ultraviolet visible diffuse reflectance spectrum(UV-vis). The results indicate that the two catalysts have good thermal stability;the crystallization temperature of TiO2 has been delayed and the phase change has been restrained because carbon nanotubes were doped into TiO2. Compared with pure TiO2, the absorptions of the composite photocatalysts were red-shifted obviously. The photocatalytic performance for hydrogen production is p-MWNTs/ ZnTPP-TiO2﹥p-MWNTs-TiO2﹥P25﹥TiO2.3. D-A type porphyrin dye molecule (A), the electron acceptor group is rhodanine acetic acid and the electron donor group is porphyrin, was synthesized and applied as photosensitizer to DSC. Its light physics and the electro-optic chemical property have studied, and the TiO2 electrode was sensitized by porphyrin dyes. The result showed that the photoelectric conversion efficiency of the solar cell was sensitized by dye A in THF is 0.326%. The photoelectric conversion efficiency of the solar cell was sensitized by N719 is 1.179% under the same testing condition.