Preparation Of Organic/Inorganic Janus Composites And Research Of Their Properties

Interfacial reaction is an important and effective method in the preparation and degradation of most organic compounds.Thus,it is important to enlarge contact area between reactants.Janus material is anisotropic in structure and chemical composition and can play an important role in the interface.In this work,two kinds of Janus materials with different morphologies were prepared by using interfacial protection method,and conducted as emulsifier to improve catalytic degradation of methyl orange reaction rate.The main contents are as follows:1.Preparation of reusable patchy Janus nanoparticles.Firstly,Fe₃O₄@Si O₂NPs was prepared by solvothermal method and sol-gel reaction.Then,it was respectively modified with phosphotungstate based ionic liquid(PW₁₂O₄₀^3--IL)and n-octyl（C₈）group by a series of reactions,such as in-situ reduction,sol-gel,Schiff-base,ion exchange reactions and so on.Thus,patchy Janus NPs with amphiphilic properties were achieved.Finally,the particle was used as interfacial catalyst to treat methyl orange wastewater.The results show that the as-prepared C₈/PW₁₂O₄₀^3--IL Janus NPs could be used as catalysts to degrade methyl orange,and their degradation could be reached to95.98%.Furthermore,the Janus NPs could be efficiently recycled in a magnetic field for their magnetic responsiveness.Meanwhile,the degradation of methyl orange was still above 90%after the C₈/PW₁₂O₄₀^3--IL NPs particles were reused 5 times.2.Preparation of temperature-responsive Janus nanosheets.Firstly,Si O₂ NPs were prepared by St（?）ber method.Then,templated microspheres were prepared by reactions of in-situ reduction and sol-gel.Finally,the tunable phosphotungstate based poly ionic liquid/poly（n-isopropylacrylamide）Janus nanosheets(PW₁₂O₄₀^3--PIL/PNIPAM Janus NS)in size were obtained via Schiff-base reaction and atom transfer radical polymerization（ATRP polymerization reaction）.The nanosheets were used as solid particle emulsifiers to emulsify oil-water mixture.Their properties of temperature responsiveness were investigated by the change of surrounding temperature.The results show that PW₁₂O₄₀^3--PIL/PNIPAM Janus NS was acted as emulsifier for their amphiphilic properties when the mixture was 50℃.On the contrary,when the mixture was 15℃,it was demulsified for their hydrophilic.