Preparation of flower-like BiOBr-WO3-Bi2WO6 ternary hybrid with enhanced visible-light photocatalytic activity

The flower-like BiOBr-WO3-Bi2WO6 (BOB-WO-BWO) ternary hybrids were designed and synthesized by an effective two-step approach. Specifically, WO3 decorated Bi2WO6 were prepared by one-step hydrothermal method and subsequent BiOBr layer via a cost-effective process. The photocatalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDS) and UV-vis diffuse reflectance spectroscopy (DRS) etc. The results indicated that WO3 nanoparticles and BiOBr small nanoplates could be dispersed on the surface of flower-like Bi2WO6 and the BiOBr-WO3-Bi2WO6 ternary hybrids with suitable BiOBr content showed higher photocatalytic activity than that of pure Bi2WO6. The enhanced photocatalytic activity of the BiOBr-WO3-Bi2WO6 was attributed to the cascade electrons transfer from Bi2WO6 to BiOBr and then to WO3 through the interfacial potential gradient in the ternary hybrid which prolong the lifetime of photo-generated charges. The photoluminescence and photo-electrochemical measurement have also verified that the suitable band potential of Bi2WO6, WO3 and BiOBr could help to achieve the efficient separation of photo-generated charges in the composite.