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

Highlights: • BiOBr/MoS₂/GO heterojunction composites were fabricated by hybridization with 20 wt% MoS₂/GO. • The band-gap energy of the bare BiOBr was obviously reduced by hybridization with MoS₂/GO. • BiOBr/MoS₂/GO composites could effectively degrade TCs of 98% within 40 min. • Holes (h⁺) were proven to be the more important active species in the degradation process. 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), and superoxide radicals (O²⁻) played crucial roles in photocatalytic OTC degradation. Further, Possible transformation pathway and photocatalytic mechanism were proposed by investigating the intermediates in OTC degradation process.