Performance of sunlight responsive WO3/AgBr heterojunction photocatalyst toward degradation of Rhodamine B dye and ofloxacin antibiotic.

A sunlight responsive WO 3 /AgBr heterojunction photocatalyst was prepared using hydrothermal and chemical precipitation methods. The photocatalyst with band gap of 2.93 eV exhibited high efficiency of 86% toward degradation Rhodamine B (RhB) dye under visible light. Interestingly, nearly complete degradation of RhB dye and ofloxacin (OFL) antibiotic under natural sunlight was achieved. Creation of the WO 3 /AgBr heterojunction is a promising strategy for enhancement of the photoactivity. This may be due to a decrease of charge carrier recombination rate at the interface and an increase in visible light absorption range of the resultant photocatalyst in comparison to those obtained from the pristine photocatalysts. Photogenerated hole plays the major role in photodegradation of the pollutant. The photocatalyst remains stable and still shows high efficiency after five consecutive cycles confirming its excellent cycling ability. This research demonstrates a promising performance of the sunlight active WO 3 /AgBr heterojunction photocatalyst for detoxification of dye and antibiotic in wastewater by utilization of an economical solar energy. [Display omitted] • A heterojunction photocatalyst based on WO3/AgBr was successfully prepared. • Complete removal of Rhodamine B (RhB) dye under natural solar light was achieved. • The photocatalytic degradation of both dye and antibiotic follows the first-order reaction. • The photocatalyst shows excellent structural stability and cycling ability after five cycles. [ABSTRACT FROM AUTHOR]