Synthesis of monoclinic clinobisvanite BiVO4 for effective visible-light degradation of antibiotics in water: Photocatalytic performance, reaction kinetics, and mechanism

This work attempts to remediate amoxicillin (AMX) as a long-life antibiotic model in aquatic environments using the BiVO4 (BVO) semiconductor photocatalyst. Monoclinic clinobisvanite BVO materials (BVO90, BVO120, BVO150, and BVO180) were prepared by the hydrothermal method at different calcination temperatures (90, 120, 150, and 180 °C). The homogeneous BVO150 particles with a visible-light-response bandgap energy of 2.36 eV showed the highest performance for AMX photodegradation within the as-prepared catalyst. AMX degradation in the solutions containing an initial AMX concentration of ≤10 ppm and a BVO150 dosage of ≥50 mg/L at pH 4 demonstrated a photodegradation efficiency of ≥93 % after 120 min. Moreover, AMX degradation on BVO photocatalysts also followed a pseudo-first-order kinetic model. The evaluation of BVO150 before and after five cycles of AMX photodegradation exhibited good durability and stability of materials. Finally, based on the data obtained from product analyses, a proposed mechanism and degradation pathway were discussed.