In situ co-precipitation for the synthesis of an Ag/AgBr/Bi5O7I heterojunction for enhanced visible-light photocatalysis

Abstract An Ag/AgBr/Bi 5 O 7 I heterojunction was developed using a simple in situ co-precipitation method. Ag/AgBr nanoparticles were tightly bound to Bi 5 O 7 I, improving charge transfer at the heterojunction interface. The photocatalytic activities of the Ag/AgBr/Bi 5 O 7 I composites were studied by monitoring the photodegradation of Rhodamine B (RhB) and through the generation of a transient photocurrent under visible-light irradiation (λ > 420 nm). The Ag/AgBr/Bi 5 O 7 I composites displayed enhanced photocatalytic activities compared to either pure Ag/AgBr or Bi 5 O 7 I. Charge carrier behavior was investigated using electrochemical impedance spectroscopy (EIS) which indicated the enhanced separation and transfer of photogenerated electrons and holes, thus giving to the higher photocatalytic activity. The high-performance semiconductor heterojunction developed in this work is a good candidate for photocatalytic application.