Preparation And Catalytic Properties Of Inorganic Semiconductor/polymer Nanocomposites

In the past few decades,photocatalysis,as a green safety technology,has attracted the attention of many scholars and has been widely used in the field of solar energy conversion and environmental purification.In photocatalytic reactions,conventional semiconductor materials such as ZnO and TiO₂ have been intensively studied as photocatalysts.However,these semiconductor materials can only absorb ultraviolet light due to their wide band gap characteristics,reducing their photocatalytic efficiency under sunlight.To this end,researchers usually modify the semiconductor material and other materials,the modified composite material broadens the light absorption range,and the generated electrons and holes are more easily separated,which greatly enhances the semiconductor light.Catalytic efficiency.In addition,from the practical point of view,the ability to repeat recycling is a challenge for semiconductor composites.In this paper,Ag-Ag₃PO₄/PAN and SnS₂/PANI are studied,and the research on the low visible light utilization rate of the material and the low photocatalytic efficiency of electrons and holes are easy to recover,and the research results are as follows:In this study,Ag-Ag₃PO₄ network nanostructures based on electrospun polyacrylonitrile（PAN）nanofibers were prepared by precipitation and reduction methods.The Ag-Ag₃PO₄/PAN material successfully obtained by X-ray diffraction and X-ray photoelectron spectroscopy.The microstructure of the composite nanomaterials can be clearly observed by scanning electron microscopy.UV-visible diffuse reflectance spectroscopy indicated that the visible light absorption capacity of Ag-Ag₃PO₄/PAN composite nanomaterials was higher than that of Ag/PAN and Ag₃PO₄/PAN materials.The prepared Ag-Ag₃PO₄/PAN composite nanomaterial was sterilized against Gram-negative bacteria E.coli and Gram-positive bacteria S.aureus.The results show that the Ag Ag₃PO₄/PAN composite nanomaterials have better sterilization activity against E.coli and S.aureus than Ag/PAN and Ag₃PO₄/PAN under visible and dark conditions.This is because the Ag-Ag₃PO₄/PAN system reduces the composite probability of electron holes and improves the photocatalytic efficiency of visible light.Under visible light conditions,Ag-Ag₃PO₄/PAN completely inactivated E.coli cells within 90 min and completely inactivated S.aureus within 150 min.The recovery of composite nanomaterials after repeated use for four times is still not less than 90%.In addition,the PAN nanofibers have a large continuous network structure to make the Ag-Ag₃PO₄/PAN composite nanomaterials more easily separated from the solution.The SnS₂/PANI composite nanomaterial was prepared by a solvothermal-oxidation polymerization method.The characteristics of SnS₂/PANI composite nanomaterials have been successfully verified by XRD,SEM and XPS.The prepared SnS₂/PANI composite nanomaterial was degraded to the dye MB solution to verify its photocatalytic ability.By changing different process parameters,such as:aniline loading,initial pH of MB solution,initial concentration of MB solution,catalyst dosage.It is proved that the visible light catalysis ability of SnS₂/PANI is better than that of pure SnS₂.SnS₂ is a stable visible light catalyst,but it is disadvantageous due to the easy recombination of electrons and holes.When combined with the conductive polymer PANI with good charge transport capability,PANI and SnS₂ have a matching electron energy band,which facilitates the separation and transfer of electrons and holes of SnS₂,and improves the photocatalytic activity.After repeated use of SnS₂/PANI composite nanomaterials for four times,the photocatalytic effect is still not less than 90%.Through the above research,it can be concluded that the prepared SnS₂/PANI nanocomposites have high performance,easy recycling and reusability.