Fabrication of Cu2O-RGO/BiVO4 nanocomposite for simultaneous photocatalytic CO2 reduction and benzyl alcohol oxidation under visible light

Abstract Cu 2 O-RGO/BiVO 4 nanocomposite was obtained via a thermal treatment of Cu precursor in the presence of the pre-obtained RGO/BiVO 4 . The product was fully characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM) and UV–vis diffuse reflectance spectroscopy (DRS). It was found that olive-shaped BiVO 4 of ca. 1.0–1.2 μm as well as small nanoparticles of Cu 2 O with a dimension of 40–50 nm were deposited on the surface of RGO. The as-formed Cu 2 O-RGO/BiVO 4 nanocomposite exhibited superior photocatalytic activity for simultaneous CO 2 reduction and benzyl alcohol oxidation under visible-light irradiation, as compared with bare Cu 2 O and RGO/BiVO 4 nanocomposite. The superior photocatalytic performance observed over Cu 2 O-RGO/BiVO 4 nanocomposite may be ascribed to the existence of the Z-Scheme charge transfer pathway in the nanocomposite, i.e., the photogenerated electrons transferred from BiVO 4 to Cu 2 O to recombine with the photogenerated holes via RGO acting as a good electron mediator. The study demonstrates a high potential of using RGO to fabricate Z-Scheme photocatalytic systems for a variety of photocatalytic applications.