Synthesis and characterization of Fe3O4/ZnO-GO nanocomposites with improved photocatalytic degradation methyl orange under visible light irradiation

To improve the photocatalytic property and recovery rate of existing ZnO materials, a magnetically separable heterostructure photocatalytic composed of GO sheets and nanohybrid Fe3O4/ZnO material was synthesized by a simple low-temperature chemical synthesis process. This synthesis enables simultaneous decoration of Fe3O4/ZnO spheres on both sides of the GO sheets. As a result, the Tauc's plot revealed the band gap of Fe3O4/ZnO-GO sample decreases to 2.07 eV from 3.38 eV of ZnO. This smaller energy band gap and slower recombination rate of electron-hole pairs greatly improve the photocatalytic activity of the Fe3O4/ZnO-GO complex through the wider visible light absorption range. The photocatalytic reaction rate of the pure ZnO photocatalyst is 4.84 x 10(-3) min(-1), for Fe3O4/ZnO composite is 1.564 x 10(-2) min(-1) and for Fe3O4/ZnO-GO composite is 5.558 x 10(-2) min(-1). The stability and recovery rate and photocatalytic property retention also greatly improved from ZnO-only photocatalyst. The photocatalytic reactivity of Fe3O4/ZnO-GO nanocomposite structure reaches 92.8% efficiency on the first run and was at 75% efficiency after the four cycling. (C) 2017 Elsevier B.V. All rights reserved.