FacileConstruction of Heterostructured BiVO4–ZnO and ItsDual Application of Greater Solar PhotocatalyticActivity and Self-Cleaning Property.

Developmentof coupled semiconductor oxides makes a significantadvancement in catalytic functional materials. In this article, wereport the preparation of nanobundle-shaped BiVO4–ZnOphotocatalyst by a simple hydrothermal process followed by thermaldecomposition. The photocatalyst was characterized by X-ray powderdiffraction (XRD), high-resolution scanning electron microscopy (HR-SEM),field emission scanning electron microscopy (FE-SEM), energy-dispersivespectroscopy (EDS), transmission electron microscopy (TEM), high-resolutiontransmission electron microscopy (HR-TEM), X-ray photoelectron spectroscopy(XPS), photoluminescence spectroscopy (PL), and UV–vis diffusereflectance spectroscopy (DRS). The XRD pattern confirmed formationof monoclinic scheelite BiVO4and the hexagonal wurtzitestructure of ZnO. HR-SEM images show nanobundle-like structure, andthe size of the nanospheres ranges from 20 to 40 nm. BiVO4–ZnO has increased absorption in the UV and visible regionwhen compared to ZnO. The catalytic activity of BiVO4–ZnOwas evaluated by the photodegradation of Acid Violet 7 (AV 7), EvensBlue (EB), and Reactive Red 120 (RR 120). The results revealed thatthe photocatalytic activity of BiVO4–ZnO was muchhigher than that of ZnO, BiVO4, and TiO2–P25under natural sunlight. BiVO4–ZnO is more advantageousthan ZnO and BiVO4in the degradation of AV 7, EB, andRR 120 because it has maximum efficiency at neutral pH 7. BiVO4–ZnO was found to be stable and reusable without appreciableloss of catalytic activity up to four consecutive cycles. The self-cleaningproperty of BiVO4–ZnO has been evaluated using contactangle measurements. Our results provide some new insights on the performanceof solar active photocatalysts on environmental remediation. [ABSTRACT FROM AUTHOR]