An oil-in-water self-assembly synthesis, characterization and photocatalytic properties of nano Ag@AgBr sensitized K2Ti4O9

Nano-sized plasmonic Ag@AgBr sensitized K2Ti4O9 composite photocatalysts (hereafter designated as Ag@AgBr/K2Ti4O9) was synthesized via a facile oil-in-water self-assembly method. The photocatalytic activity of the prepared materials for methylene blue (MB) degradation was examined under visible light irradiation. The results reveal that the size of Ag@AgBr, which evenly dispersed on the surface of K2Ti4O9, distributes about 20 nm. The UV-vis diffuse reflectance spectra indicate that Ag@AgBr/K2Ti4O9 samples have a significantly enhanced optical absorption in 420-800 nm. The photocatalytic activities of the Ag@AgBr/K2Ti4O9 samples increase first and then decrease with increasing amount of loading Ag@AgBr and the Ag@AgBr(10 wt%)/K2Ti4O9 sample exhibits the best photocatalytic activity and 95.75% MB was degraded after irradiation for 90 min. Additionally, studies performed using radical scavengers indicated that h+, ·OH and Br0 acted as the main reactive species.