Bi3.64Mo0.36O6.55/Bi4O5I2 S-scheme heterojunction boosting antibiotic photodegradation: Insights from interface to performance

A 0D/3D Bi3.64Mo0.36O6.55/Bi4O5I2 (BIM) S-scheme heterojunction with strong interfacial interactions was synthesized by calcination followed by hydrothermal treatment. The experimental and analytical results reveal that the S-scheme heterojunction not only imparts photothermal properties to the composite, but also acts as an electron transport bridge to promote photogenerated charge transfer, which in turn promotes the oxidative capacity of the catalyst. In a visible light excited heterojunction system, BIM-34 can degrade tetracycline (TC) up to 91.6% and also remove other contaminants up to more than 90% within 60 min. The analysis of the S-scheme heterojunction was further validated by X-ray photoelectron spectroscopy (XPS), quenching experiments, electron paramagnetic resonance (ESR) and DFT theoretical calculations. This work provides a viable strategy for designing S-scheme heterojunction with strong interface interactions photocatalysts for antibiotics removing.