Preparation,Characterization And Photocatalytic Properties Of Polyoxometalate/Polyaniline/V₂O₅ Composites

The CuW₁₁Al and the Ni W₁₁ B were synthesized by direct chemical synthesis,then PANI/V₂O₅ was synthesized by chemical oxidation method with?NH4?2S2O8 as oxidant,finally the CuW₁₁ Al and the Ni W₁₁ B with PANI/V₂O₅ were compounded by electrostatic self-assembly method,and the CuW₁₁Al/PANI/V₂O₅ and the NiW₁₁B/PANI/V₂O₅ were synthesized.The composite materials' composition,appearance,structure,nature were characterized by methods of IR,UV,XRD,XPS,SEM,nitrogen adsorption and TG-DTG.The results show that: the CuW₁₁Al/PANI/V₂O₅ and the Ni W₁₁B/PANI/V₂O₅ were proved that they still maintain the Keggin structure of heteropolyanions by methods of IR,UV,XRD,XPS.The synthesized samples were proved to be highly stable by TG-DTG.SEM shows that the two composites are evenly distributed and the order is regular.In this experiment,the photocatalytic properties of the composites of the CuW₁₁Al/PANI/V₂O₅ and the NiW₁₁B/PANI/V₂O₅ were studied,and photocatalytic experiments of gentian violet and methylene blue were carried out using them as catalyst respectively.The effects of methylene blue and gentian violet's decolorization rate were studied under conditions of different pH,different catalyst dosage and different initial concentration.The optimum conditions for the photocatalytic degradation of the CuW₁₁Al/PANI/V₂O₅ and the NiW₁₁B/PANI/V₂O₅ to methylene blue and gentian violet were determined.Then under optimum conditions,the photocatalytic activity of CuW₁₁Al/PANI/V₂O₅ and NiW₁₁B/PANI/V₂O₅ was compared with their corresponding heteropolyacid and PANI/V₂O₅.The experimental results show that the catalytic activity of the CuW₁₁Al/PANI/V₂O₅ and the NiW₁₁B/PANI/V₂O₅ was superior to heteropolyacid and PANI/V₂O₅,and the order of catalytic activity is: the CuW₁₁Al/PANI/V₂O₅ and the NiW₁₁B/PANI/V₂O₅ > heteropolyacid > PANI/V₂O₅.The photocatalytic activity of CuW₁₁Al/PANI/V₂O₅,NiW₁₁B/PANI/V₂O₅ was also investigated under different light sources and the photocatalytic cycling experiments of them were carried out.