Synthesis Of Zn（Ⅱ） Porphyrin-Sensitized TiO₂ Composites And Their Photocatalytic Activity Under Visible Light

Porphyrin and its derivatives is a kind of organic compounds, which has good big ring-plane conjugate and aromaticity structure, and can be found anywhere in nature life. In fact, Porphyrin and its derivatives play a particularly important role in our life. Those features enable it to be widely researched and applied, such as the chromogenic agent, photoelectric composite materials, light catalyst, anti-cancer drugs, and superconductors. Therefore, in this paper, a indigo blue target product 5-(4-hydroxy) phenyl-10,15,20-trinaphthylporphyrin was synthesized by Adler-Longo based on the photocatalysis of porphyrin and its derivatives in visible light even infrared light, and got the final target product Zn(Ⅱ)-5-(4-carboxylmildmethoxy) phenyl-10,15,20-trinaphthylporphyrin (CmpTNPP(Zn)) through two hydrated zinc acetate.The attractions of graphene are not only the unique two-dimensional structure, but also the superior electronic transmission performance and excellent physico-chemical properties. Graphene, which is peeled from graphene oxide under ultrasonic, is used for synthesizing GE/TiO2 powders by sedimentation methods, and added CmpTNPP(Zn) to get CmpTNPP(Zn)/GE/TiO2 composites with impregnation method, then the catalytic properties was studied under visible light and the degradation mechanism was discussed.At the same time, the method of sedimentation was also used for AlO2/TiO2, ZrO2/TiO2, and ZnS/TiO2 with (CmpTNPP(Zn)) to obtain different components of porphyrin sensitizing composite materials. These composites were characterized by Scanning Electron Microscope (SEM), X-ray Diffraction (XRD), Fourier Transform Infrared Spectrophotometer (FT-IR), Thermalgravimetry (TG), and UV-Vis Diffuse Reflectance Spectrum (DRS). And then the methylene blue (MB) solution was used as simulated wastewater to evaluate the photocatalytic activity of the composite material under visible light irradiation. The results shown that the CmpTNPP(Zn) could effectively improve the absorption of visible light of semiconductor doped powder, and greatly improve the photocatalytic activity of the composites. the degradation of methylene blue rates have reached more than 95% within 80 min. it’s found that the composite material still keep certain degradation rate after reuse five times. What’s more, as the successive use of composite materials, these composite materials gradually become saturated adsorption of MB, and gradually tended to the degradation of MB of pseudo first order kinetics process.