Fabrication of visible-light photoactive TiO2/BiVO4 composite for photocatalytic degradation of ciprofloxacin

Pure {BiVO4} and three {TiO2/BiVO4} composite photocatalysts with {Bi³⁺:Ti⁴⁺} molar ratios of 1:1, 2:1, and 4:1 were readily synthesized for the first time using a one-pot hydrothermal procedure for the photodegradation of ciprofloxacin. Conducting the hydrothermal reaction in a basic medium yielded single-phase scheelite monoclinic polymorphic {BiVO4} (ms- {BiVO4} ) in the composite samples. Microstructural analysis showed spherical {TiO2} nanoparticles with an average grain size of 120 nm embedded on the surface of {BiVO4} nanoplates. The optimized composite exhibited a ciprofloxacin photodegradation reaction rate constant was about 3.8 times higher than that of the pure {BiVO4} sample. This significant enhancement is attributed to the formation of a {TiO2/BiVO4} heterojunction, which promotes efficient charge separation. This research expands the knowledge on designing of {BiVO4} -rich composites (with {Bi³⁺:Ti⁴⁺} molar ratio ≥ 1:1) via heterogeneous junction engineering to enhance photocatalytic activity beyond that of pure {BiVO4} . This research also provided a perspective on using the {BiVO4} -rich composites as effective photocatalysts as degradation of antibiotics in aqueous media under visible-light irradiation.