The Preparation And Photocatalytic Activity Of Ag@AgX Composition Materials

Ag@AgX(X = Cl, Br, I) exhibiting surface plasmon resonance(SPR) has been shown to be effective for the degradation of organic pollutants. However, these catalysts are associated to certain limitations such as easily aggregation, impractical cost et. al. These drawbacks can be overcome through the use of silver/silver halide composite materials. Combining Ag@AgX with layered semiconductor material could form Nano dimensional junctions, provide more active sites, and promoted the efficient separation of electron-hole pairs. This study may provide a new insight for the synthesis of photocatalysts with high visible light activities.Nano-sized Plasmonic Ag@AgCl surface-modified K2Ti4O9 composite photocatalysts(hereafter designated as Ag@AgCl/K2Ti4O9) were synthesized via a facile oil-in-water self-assembly method. The size of Ag@AgCl on the surface of K2Ti4O9 distributes about 20~50 nm. The Ag@AgCl(20 wt%)/K2Ti4O9 sample exhibits the best photocatalytic activity and 94.47 % Rh B was degraded after irradiation for 2 hours.Ag@AgBr nanoparticle-sensitized K2Ti4O9 composite photocatalysts could be prepared by a facile precipitation-photoreduction method. The size of Ag@AgBr on the surface of K2Ti4O9 was distributed in the range of 20~50 nm. Approximately 95.89 % of RhB was degraded by Ag@AgBr(20 wt.%)/K2Ti4O9 after irradiation for 1 h.Ag@AgI-sensitized K2Ti4O9 photocatalysts were synthesized via a facile hydrothermal method. The size of Ag@AgI nanoparticles on the surface of K2Ti4O9, was distributed in the range of 100~200 nm. Ag@AgI(15 wt%)/K2Ti4O9 exhibited the highest photocatalytic activity, degrading 95.26% of MB after 2 hours of irradiation.Quantum dots(QDs) Ag@AgCl decorated on the surface of flower-like Bi2WO6(hereafter designated Ag@AgCl/Bi2WO6) were prepared via a facile oil-in-water selfassembly method. QDs Ag@AgCl was observed to be evenly dispersed on the surface of Bi2WO6, and was approximately 10 nm in size. Ag@AgCl(20 wt%)/Bi2WO6 exhibited the best photocatalytic activity, degrading 97.61 % RhB after irradiation for 2 hours.