Visible-light-driven Ag/AgBr/ZnFe2O4 composites with excellent photocatalytic activity for E. coli disinfection and organic pollutant degradation.

Visible-light-driven (VLD) Ag/AgBr/ZnFe2O4 composites with different weight ratios of ZnFe2O4 were synthesized via a facile hydrothermal method. The ZnFe2O4 was evenly dispersed on the surface of Ag/AgBr particles with the diameter about 20 nm. The obtained Ag/AgBr/ZnFe2O4 composites exhibited the high bacterial disinfection efficiency and inactivated bacteria after 120 min visible illumination, which was better than those of with pure ZnFe2O4 and Ag/AgBr. Due to the introduction of ZnFe2O4, the Ag/AgBr/ZnFe2O4 inactivated bacterial cells through the generation of H2O2, which generated from the electron reduction on the conduction band of ZnFe2O4 in the system. The photocatalytic experiments indicated that as-prepared samples showed the good photocatalytic performance toward degradation of methyl orange (MO) dye. In a word, the Ag/AgBr/ZnFe2O4 composites, as the antibacterial photocatalyst, is a promising candidate material in wastewater decontamination.