Graphene-zinc oxide nanocomposites (G-ZnO NCs): Synthesis, characterization and their photocatalytic degradation of dye molecules

Highly pure zinc oxide nanoparticles (ZnO NPs) and graphene-zinc oxide nanocomposites (G-ZnO NCs) were synthesized via chemical precipitation method. The structure, morphology, and composition of the synthesized ZnO NPs and G-ZnO NCs were characterized by using fourier transfer infrared spectroscopy, X-ray diffraction spectroscopy, Raman spectroscopy, scanning electron microscopy and transmission electron microscopy (TEM). The TEM images revealed that the diameter of ZnO NPs is 8–12 nm and homogeneously dispersed onto the surface of graphene sheets. The photocatalytic degradation efficiency of the synthesized G-ZnO NCs against rhodamine-B (Rh-B), methylene blue (MB) and methyl orange (MO) was quantified under visible light irradiation. The irradiation time required for complete removal of the dyes are dependent on dye molecules (MB, MO and Rh-B) and their interaction with the prepared ZnO NPs and G-ZnO NCs. The synthesized NCs were highly efficient for the removal of Rh-B compared to other tested dyes. Hence, the synthesized G-ZnO NCs could be used for environmental dye remediation.