Study On The Preparation Of PDINH Series Organic-inorganic Photocatalyst And Its Degradation Performance Of Phenol

In this thesis,organic 3,4,9,10-tetracarbonate diimide（PDINH）was used as the main material to prepare organic-inorganic photocatalyst supported by inorganic Bi2WO6 and TiO2.Thus,the photocatalytic activity of organic-inorganic photocatalysts can be improved by increasing the photo utilization rate of organic-inorganic photocatalysts and reducing the recombination rate of electrons and holes in the photocatalysts.The results of experiments show that the organic-inorganic composite photocatalyst has excellent photocatalytic ability to degrade phenol.The visible light catalytic material PDINH/Bi2WO6 was synthesized by hydrothermal method based on PDINH nano-supramolecules.Due to the insufficient utilization rate of sunlight of n-type semiconductor material PDINH,and the low recovery rate of this kind of photocatalytic material due to its good dispersion in water and ethanol was found by experiments,PDINH has not been widely studied and applied in practical production.In order to improve the shortcoming of PDINH supra-molecular（PDINH）,two substances,Bi（NO3）3 and Na2WO4,were added into the reactor,and inorganic Bi2WO6 was loaded on PDINH to prepare the organic-inorganic photocatalyst PDINH/Bi2WO6,which can degrade phenol.Through a variety of characterization,it is concluded that the close contact interface between PDINH and Bi2WO6 is formed through intermolecularπ-πstalling and hydrogen bond interaction.Compared with PDINH or Bi2WO6 alone,the photocatalytic activity of PDINH/Bi2WO6 for phenol degradation（6 ppm）was improved.It is proved that the energy band matching and the closely integrated interface of the two nanomaterials improve the photocatalyst degradation ability of phenol.In addition,the PDINH supramolecule as a carrier also enhances the stability of Bi2WO6,thus improving its recycling.Nano-anatase TiO2 supported by PDINH was self-assembled to synthesize the PDINH/TiO2 organic-inorganic sheet photocatalyst with enhanced photocatalytic activity.The-CO···H hydrogen bond between PDINH and TiO2 molecules can realize effective long-range electron delocalization in the PDINH/TiO2 nano-photocatalyst synthesized,which accelerates the migration and separation of photoelectric charge,and makes the composite photocatalyst possess remarkable photocatalytic properties.In this study,the photocatalytic degradation of phenol by PDINH/TiO2 was investigated for the first time,and it was proved that the organic-inorganic PDINH/TiO2 nanocomposite showed a rapid degradation efficiency of phenol within 6 h under sunlight.Due to the-CO···H hydrogen bond interaction between PDINH and TiO2 molecules,the photocatalytic performance of the composite photocatalyst has been greatly improved.Finally,based on the previous work,an organic-organic composite photocatalyst PDINH/TiO2/Bi2WO6（P/T/B）was prepared by self-assembly method in this study.Under acidic conditions,Bi2WO6 and TiO2were supported on PDINH supramolecular support by means of-CO···H hydrogen bond interaction between PDINH and TiO₂ molecules,π-πstalling between PDINH molecules and lone electron attraction of Bi2WO6 oxygen atom.The photocatalytic performance of P/T/B organic-organic composite photocatalyst in the degradation of 6 ppm phenol solution under simulated sunlight and the stability of P/T/B photocatalyst in the degradation process were also discussed.In addition,the mechanisms of photocatalytic reactions observed in this study are briefly described.