High proportion ZnO/CuO nanocomposites: Synthesis, structural and optical properties, and their photocatalytic behavior

High proportion ZnO/CuO nanocomposites synthesize through sol-gel method acquire structure, morphology, optical, and catalytic properties of the nanocomposites were examined with several characterization techniques. X-ray diffraction and Raman spectroscopy confirmed the formation of two-phase nanocomposites (ZnO- hexagonal wurtzite /CuO-Monoclinic) and stress was detected in the crystalline lattice of ZnO. Nanocomposites with semi-spheroidal shape were observed using scanning electron microscopy and transmission electron microscopy. Optical and photoluminescence studies show the existence of defects in the nanocomposites. Photocatalytic activity of the as-synthesized ZnO, CuO nanoparticles and ZnO/CuO nanocomposites were studied by the photodegradation of methylene blue (MB) under visible radiation. Besides, it was possible observed that the surface modification and the coupling of nanomaterials influenced photocatalysis. The results indicate that an increase in the ZnO content can improve the efficiency; however a modification in the form of incorporating the zinc oxide on copper oxide generates an increase of three times on photocatalytic activity.