Synthesis and Characterization of Graphene Oxide/Zinc Oxide (GO/ZnO) Nanocomposite and Its Utilization for Photocatalytic Degradation of Basic Fuchsin Dye

Abstract

In this study, graphene oxide/zinc oxide (GO/ZnO) nanocomposite was prepared by the decoration of thermally expanded and chemically oxidized graphite oxide nanosheets with zinc oxide (ZnO) nanoparticles synthesized via two-step sol-gel deposition method and used as an effective photocatalyst for degradation of basic fuchsin (BF) dye. Structural properties of GO/ZnO nanocomposite were characterized with X-Ray Diffraction (XRD), Fourier-Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM) methods, and Brunauer-Emmett-Teller (BET) surface area measurement. It was found that the GO/ZnO nanocomposite formed a two-dimensional (2D) structure having a composition of 0.54GO/0.46ZnO (w/w) and average ZnO partic le size of 25-30 nm. The band gap of ZnO nanoparticles onto GO nanosheets was found to be 3.25 eV while that of bulk ZnO nanoparticles was determined as 3.70 eV. Photocatalytic degradation works were performed into a UV-chamber by following the concentration of BF dye. Degradation reaction was modeled with the Langmuir-Hinshelwood pseudo first-order kinetic model. GO/ZnO nanocomposite increased the apparent reaction rate constant (k) about three times compared to bulk ZnO nanoparticles under UV light.