Preparation and Photocatalytic Application of the Composites PMo₁₂/AgNPs Based on Polyoxometalates

Supported catalysts, consisting of PMo₁₂ immobilized on silver nanomaterials at different recombination time and the silver nanomaterials with different template sodium citrate amount characterized by FT-IR, XRD, SEM, UV-vis and other test methods. The results show that the AgNPs are relatively uniformed with sizes between 100-300 nm when the sodium citrate addition amount is 9.0 mL. As the reaction time of PMo₁₂/AgNPs increases, the adhesion of AgNPs on the surface of PMo₁₂ becomes more complete. Using PMo₁₂ and PMo₁₂/AgNPs composite materials as catalysts, methylene blue (MB) is photocatalytically degraded under simulated visible light conditions. The results show that PMo₁₂ can catalyze MB effectively, and the decolorization rate reached 98.6% when the catalyst content is 2 g/L, the solution pH is 3 and the MB concentration is 5 mg/L. Under the same experimental conditions, photocatalytic performance of the PMo₁₂/AgNPs system is better than that of the PMo₁₂ further improved the photocatalytic degradation effect of the MB solution with a decolorization rate of 100%. The composite still keeps good photocatalytic activity and stability after three cycles of use. Finally, the catalytic mechanism of the POMs composite material is preliminarily discussed.