Photocatalytic CO2 reduction performance of Z-scheme Ag-Cu2O/BiVO4 photocatalyst

A Z-scheme heterojunction photocatalyst Ag-Cu2O/BiVO4 was successfully constructed with effective charge carrier separation/transfer by uniformly encapsulating Cu2O nanospheres and Ag nanoparticles on the surface of decahedral BiVO4 using a simple chemical reduction deposition strategy. The photo-reduction of carbon dioxide reaction result indicated that the as-prepared Ag-Cu2O/BiVO4 heterostructure exhibited excellent activity of photo-reduction CO2 with the CO yield of 5.37 mu mol center dot g(-1)center dot h(-1), about 35.8 times and 6.25 times of original BiVO4 and Cu2O, respectively. Ag-Cu2O/BiVO4 was characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDS), UV-Vis diffuse reflectance absorption spectra (UV-Vis DRS), photoluminescence (PL) spectra, transient photocurrent responses (TPC), and electrochemical impedance spectroscopy (EIS), and the possible reaction mechanism for the reduction of CO2 in the photocatalytic system was proposed.