Facile Fabrication of Z-Scheme Bi₂WO₆/WO₃ Composites for Efficient Photodegradation of Bisphenol A with Peroxymonosulfate Activation

The rational fabrication of direct Z-scheme heterostructures photocatalysts is a pivotal strategy to boost the interfacial charge migration and separation. Herein, direct Z-scheme Bi₂WO₆/WO₃ composites were rationally fabricated for the degradation of bisphenol A combined with the activation of peroxymonosulfate (PMS). The tight interface contact between Bi₂WO₆ and WO₃ was successfully formed by the in situ epitaxial growth of ultrathin Bi₂WO₆ nanosheets at the surface of WO₃ nanorods. The Bi₂WO₆/WO₃ composite presented highly efficient catalytic performance toward degradation of BPA with PMS activation as compared to the WO₃ and Bi₂WO₆. PMS can dramatically boost the photocatalytic activity of the composites. Moreover, the results of active radical scavenging experiments revealed that h⁺, •O₂^-, and •SO₄^- are critical active species in the photodegradation reaction. Finally, the photocatalytic mechanism for the degradation of BPA is also discussed in detail. The great improvement of photocatalytic performance should be ascribed to the effective formation of the direct Z-scheme heterojunctions between Bi₂WO₆ and WO₃, resulting in improved light absorption, an efficient transfer and separation of photoinduced charge carriers, and a considerable amount of the electrons and holes with strong reduction and oxidation abilities. The study might provide new inspirations to design and construct heterostructured nanomaterials with outstanding photoactivity for environmental remediation.