Fabrication of silver bromide rods via an oil-in-water emulsion route and their high photocatalytic activity under direct sunlight irradiation

Abstract Silver bromide (AgBr) rods with different polydispersity were first synthesized in situ in oil (dodecane)-in-water emulsion, where AgNO 3 was used as the silver ion source and tetradecyl trimethyl ammonium bromide acted as both the bromide ion source as well as the stabilizing agent. Scanning electron microscopy and X-ray diffraction techniques were carried out to characterize their morphologies and crystal structures. A morphology evolution varying with aging time showed that the AgBr rods in oil-in-water emulsion formed from nanoparticles, and the formation process was disclosed by drop-coating initially formed emulsion onto glass substrate and quick solvents evaporation. Besides, in comparison with commercial P25 (anatase 80%, rutile 20%), the as-fabricated AgBr rods presented excellent photocatalytic activities over methyl orange under direct sunlight irradiation, showing their promising potential as efficient sunlight-driven photocatalysts for organic pollutants degradation. Graphical abstract