Fabrication of BiOBr/MoS2/graphene oxide composites for efficient adsorption and photocatalytic removal of tetracycline antibiotics

Bismuth oxybromide/molybdenum disulfide/graphene oxide (BiOBr/MoS2/GO) heterojunction composites were fabricated to modulate the adsorption ability and photocatalytic degradation performance toward oxytetracycline (OTC). The flowerlike BiOBr/MoS2/GO composites demonstrated excellent photocatalytic activies for the OTC degradation. Specifically, OTC, tetracycline, chlorotetracycline, and doxycycline were simultaneously removed with degradation rates higher than 98% under visible light irradiation within 40 min. Radical trapping experiments indicated that photogenerated holes (h(+)), hydroxyl radicals ((OH)-O-center dot), and superoxide radicals (O-center dot(2-)) played crucial roles in photocatalytic OTC degradation. Further, Possible transformation pathway and photocatalytic mechanism were proposed by investigating the intermediates in OTC degradation process.

Automated summary

The BiOBr/MoS2/GO heterojunction composites showed excellent photocatalytic activity for oxytetracycline degradation, achieving degradation rates over 98% for multiple antibiotics under visible light irradiation within 40 minutes. Radical trapping experiments revealed the crucial roles of photogenerated holes, hydroxyl radicals, and superoxide radicals in the photocatalytic OTC degradation process, and a possible transformation pathway and mechanism were proposed based on the investigation of intermediates.