Integrating BaFe2O4 nanoparticles onto N-doped Bi2WO6 microspheres for eminent visible light-driven photocatalytic performance towards aquaculture contaminants and pathogens

Constructing highly effective visible light-responsive photocatalysts with robust redox capability is of great significance for remediation of environmental contaminants. Herein, a novel Z-scheme 0D/3D BFO/NBWO composite was successfully fabricated via a facile precipitation-hydrothermal approach. The physicochemical and optoelectronic properties of the obtained photocatalysts were affirmed via different characterization techniques. Under visible light irradiation, the 2-BFO/NBWO composite demonstrated the top-flight photocatalytic degradation of tetracycline (TC), which was 10.6, 6.0, 4.2 and 4.6-fold greater than those of BFO, BWO, NBWO and 2-BFO + NBWO, respectively. Such photocatalytic enhancement was primarily attributed to the acceleration of charge separation and migration in Z-scheme heterojunction. Additionally, the 2-BFO/NBWO composite displayed good versatility to pH variation in the solution, resistance to coexisting anions and humic acid as well as satisfactory reusability after five-cycle experiments. More importantly, real aquaculture effluent-containing TC, bisphenol A (BPA), malachite green (MG) and hexavalent chromium (Cr(VI)) were also successfully treated. The toxicity findings also proved that the treated aquaculture effluent appeared to have no significant noxious effect on Danio rerio after 2-BFO/NBWO photocatalysis. In addition to the examination of organic contaminants degradation, the prepared 2-BFO/NBWO composite was also effectively used to eradicate Escherichia coli (E. coli) and Bacillus cereus (B. cereus). The hydroxyl radicals were found to make predominant contributions to the photocatalytic reactions. This work gives a new avenue for fabricating Z-scheme composite photocatalysts with effective interfacial charge migration to degrade various organics and to eradicate pathogens from effluents.