A Z-scheme magnetic recyclable Ag/AgBr@CoFe2O4 photocatalyst with enhanced photocatalytic performance for pollutant and bacterial elimination

In order to construct a magnetic recyclable photocatalyst with superior photocatalytic performance and stability, Ag/AgBr photocatalysts modified by magnetic CoFe2O4 nanoparticles (NPs) were synthesized via deposition-precipitation followed by a solvothermal process. Such a synthesis strategy allows the even dispersion of CoFe2O4 NPs on the surface of Ag/AgBr. Besides, a Z-scheme photocatalyst with metallic Ag as a solid-state electron mediator was formed, which exhibits excellent photocatalytic activity and stability for photocatalytic degradation of hardly decomposed colorless phenol compounds, namely, endocrine disrupting chemical bisphenol A (BPA) and 4-chlorophenol (4-CP), in an aqueous solution. The results showed that the Ag/AgBr@CoFe2O4 composites not only exhibited enhanced photocatalytic performance but also improved stabilities. More importantly, the photocatalysts could be recycled easily by an external magnetic field. The antibacterial activity of the Ag/AgBr@CoFe2O4 composites have been investigated by eliminating Escherichia coli (E. coli) in water under visible light irradiation, and the results revealed that the Ag/AgBr@CoFe2O4 composites possessed good photocatalytic antibacterial activity. At last, the enhanced photocatalytic mechanisms were discussed by investigating the main reactive species in the photocatalytic process, which revealed that the photo-generated holes (h(+)) and O-2(center dot-) were the main reactive species.