Enhanced visible-light photocatalytic activity of FeVO₄/Bi₂WO₆ heterojunction via Z-scheme charge-transfer mechanism

The design and construction of a Z-scheme heterojunction, aiming to strengthen its redox ability for photocatalytic applications, is challenging. In this study, a series of x mol%-FeVO4/Bi2WO6 heterostructures were fabricated. FeVO4 content was tuned for enhanced organic pollutants photodegradation. The 2.5 mol%-FeVO4/Bi2WO6 photocatalyst exhibited superior photodegradation efficiency with high recyclability and stability for bisphenol A and methylene blue, which was 3.3 and 2.6 times faster than that of Bi2WO6, respectively. Moreover, the fabricated photocatalyst showed remarkable selectivity toward methylene blue as compared to that toward brilliant green and methyl orange. The photo-efficacy was enhanced owing to the close interfacial contact between Bi2WO6 and FeVO4 nanoparticles, resulting in a Z-scheme FeVO4/Bi2WO6 heterojunction, which enabled efficient charge transfer imparting strong reducing ability to the electrons for the reduction of O-2 to center dot O-2(-), and subsequent production of H2O2 and center dot OH. This work highlights a potential photocatalyst for photodegradation of environmental pollutants.