Visible-light-driven Bi2WO6/BiVO4 (BWO/BVO) heterostructures were obtained by joining BWO and BVO n-type semiconductors. A novel and green metathesis-assisted molten salt route was applied to synthesize BWO/BVO. This route is straightforward, high-yield, intermediate temperature, and was successful for obtaining BWO/BVO heterostructures with several ratios (1:1, 1:2, 2:1 w/w). Besides, the 1BWO/1BVO was decorated with Ag nanoparticles (Ag-NPs, 6 wt.%) and graphene (G, 3 wt.%), applying simple and environmentally responsible procedures. The heterostructures were characterized by XRD, Raman, UV-Vis DRS, TEM/HRTEM, PL, and Zeta potential techniques. Ag-NPs and G effectively boosted the photocatalytic activity of 1BWO/1BVO for degrading tetracycline (TC) and rhodamine B (RhB) pollutants. A lab-made 19-W blue LED photoreactor was designed, constructed, and operated to induce the photoactivity of BWO/BVO heterostructures. The low-rated power consumption of the photoreactor (0.01-0.04 kWh) vs. the percent degradation of TC or RhB (%XTC = 73, %XRhB = 100%) is one of the outstanding features of this study. Besides, scavenger tests determined that holes and superoxides are the main oxidative species that produced TC and RhB oxidation. Ag/1BWO/1BVO exhibited high stability in reuse photocatalytic cycles.
Keywords: Antibiotics; Bismuth; Dyes; Heterojunctions; Photodegradation; Visible LEDs.
© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.