Synthesis of CuO-ZnO nanophotocatalyst for visible light assisted degradation of a textile dye in aqueous solution

An attempt was made to prepare CuO/ZnO nanophotocatalyst for visible light assisted degradation of a textile dye (Acid Red 88) in aqueous solutions by wet impregnation method. The CuO/ZnO samples annealed at 550 °C for 5 h were changed from purple to grey, indicating that CuO clusters on ZnO may not be metallic Cu but it may be CuO-ZnO. Characterization using Transmission Electron Microscopy (TEM), Diffuse Reflectance Spectroscopy (DRS), X-Ray Photo Electron Spectroscopy (XPS) and X-Ray Diffraction (XRD) analysis confirms that only CuO phase is present in the as prepared sample. The prepared CuO-ZnO shows approximately 2 times more photocatalytic activity compared to that of bare ZnO and as well as enhanced photocatalytic activity in the presence of external electron acceptors such as PMS (peroxomonosulphate), PDS (peroxodisulfate), and H2O2 (hydrogen peroxide). Total organic carbon (TOC) experiments also support such enhanced activity.