Ag/AgCl/Ag2MoO4 composites for visible-light-driven photocatalysis

Ag 2 MoO 4 shows low photocatalytic activity under visible light. It would be interesting to develop Ag 2 MoO 4 -based composite/heterojunction photocatalysts working efficiently under visible light. Herein, novel Ag/AgCl/Ag 2 MoO 4 composites were obtained via photoreduction of AgCl/Ag 2 MoO 4 composites prepared by sequential precipitation. The composition, morphologies, and optical properties of the samples were studied via various characterization techniques. Photocatalytic degradation of rhodamine B (RhB), methylene blue (MB), methyl orange (MO), norfloxacin (NOF), and tetracycline hydrochloride (TC) solutions was conducted under visible-light irradiation. An optimal Ag/AgCl/Ag 2 MoO 4 catalyst showed much higher photocatalytic activity than Ag 2 MoO 4 , and it also showed reasonably fine recyclability. Through radical-capturing experiments, photogenerated holes (h + ) were determined to be the main active species whereas hydroxyl radicals ( OH) were found to play a secondary role in photocatalysis. Possible photocatalytic mechanisms were proposed.