PHOTOCATALYTIC PROPERTIES OF ZnO/CuO/Ag TERNARY COMPOSITES

Abstract

In this paper, ZnO/CuO/Ag ternary composites were successfully synthesized by hydrothermal method using Zn(NO₃)₂.6H₂O, Cu(NO₃)₂.3H₂O and AgNO₃. The composite samples were characterized using X-Ray diffraction (XRD), Scanning Electron Microscopy (SEM) and Raman spectroscopy. Their photocatalytic activities were examined using Congo Red (CR) degradation under Xenon lamp 55 W illumination. The organic dyes degradation was determined by decreasing of characteristic intensity peak in UV-Vis spectrum versus time of their solutions. In comparison with CR, the degradation of other organic dyes such as Methylene Blue (MB), Rhodamine B (RhB) and Crystal Violet (CV) was examined.  The result showed that the ZnO/CuO/Ag composite (n_Cu²⁺/n_Zn²⁺ = 0.10) exhibited higher photocatalytic activity. The degradation reaches 84.8% when the CR solution with concentration of 10 ppm and 40 mg of this composite was tested. The enhanced photocatalytic activity in mainly attributed to the construction of chemical potential gradients between proper amount of CuO and ZnO adding the intermediary role of Ag.