Flexible Metal-containing Substituents Porphyrin Synthesis And Properties Of Design Complex

Porphyrins and metalloporphyrins have attracted wide attention in recent years, due to its unique structure and perfect photosensitive properties. Porphyrin compounds not only can be used as the building blocks for the construction of diverse functional metalloporphyrinic frameworks (MPFs), but also can be used to modify semiconductor materials to prepare composite photocatalysts.Since the flexible peripheral functional groups (-COOH) of the porphyrins backbone is favorable for the generation of various MPFs desired in practical applications such as gas adsorption and selective catalysis. Firstly, we synthesized two porphyrins containing flexible functional groups (meso-tetra(ester, carboxy)),5,10,15,20-tetrakis[4-(carboethoxy-methyleneoxy)phenyl]porphyrin (H2TEMOPP) and5,10,15,20-tetrakis[4-(carboxy-methyleneoxy)phenyl]porphyrin (H2TCMOPP), and corresponding (Co(Ⅱ)、Ni(Ⅱ)、Cu(Ⅱ)、 Zn(Ⅱ)、Mn(Ⅲ)) metalloporphyrins. All the synthesized compounds were characterized by mass spectra (MS), foruier transform infrared (FT-IR), ultra violet-visible (UV-Vis),1H NMR and elemental analyses (EA), and the crystal structure of Zn(TEMOPP), Cu(TEMOPP) and Cu(TCMOPP) were obtained. Secondly, the synthesized Cu(TCMOPP) and Ni(TCMOPP) were used to construct three novel porous metalloporphyrinic frameworks:{Zn2[Cu(TCMOPP)]2}?4HN(CH3)2(1),{K2[Ni(TCMOPP)]DMF}(2) and{K2[Ni(TCMOPP)]2-(DMF)2}?DMF?H2O (3). The framework structures were analyzed and confirmed by the experimental methods, such as X-ray single crystal diffraction, X-ray diffraction (XRD), thermal gravity analysis (TGA), EA and FT-IR. The TGA indicate that the framework structures of the metalloporphyrin coordination compounds are stable below290℃. However, the properties such as gas adsorption and selective catalysis need further study.On the other hand, it is verified that porphyrins-TiO2can efficiently degrade the organic molecules in aqueous solutions. However, few work have demonstrated the accumulated patterns of porphyrin molecules on the surface of TiO2and the influence on photocatalytic activity. Herein, two copper porphyrin-TiO2composite photocatalysts were prepared and characterized by FT-IR, XRD, UV-Vis, diffuse reflectance spectroscopy (DRS) and scanning electron microscope (SEM). The photocatalytic efficiency of copper porphyrin-TiO2 photocatalysts were tested by the experiments of photocatalytic degradation of4-nitrophenol (4-NP) in aqueous solution under UV-Vis light irradiation. Furthermore, the crystal structures of porphyrins were used to predict the influence of the accumulated patterns of poiphyrin molecules on the surface of TiO2on the photocatalytic efficiency. The results indicate the accumulated patterns of porphyrin molecules on the surface of TiO2is an important factor for the photocatalytic efficiency, except for the strength of interaction between porphyrin and TiO2. These results presented here could be useful in the design of new highly efficient porphyrin-TiO2photocatalysts.