Preparation of coal-based graphene oxide/SiO2 nanosheet and loading ZnO nanorod for photocatalytic Fenton-like reaction

Abstract

Preparation of new type coal-based carbon nanomaterials and its application in Fenton-like photocatalytic organic pollutant degradation was presented here. The study promoted the high value-added use of coal and extended Fenton-like research system. The coal with high silicon content from Wucaiwan, Xinjiang, China was used as carbon and silicon source. The coal-based graphene oxide (GO) was obtained via the oxidation and exfoliation of crystal graphite in coal under the ultrasonic oxidation treatment by the modified Hummers method. In this way, the natural silicon in coal was converted into the silica dioxide (SiO2) and in situ linked to the surface of the GO sheet by the surface hydroxyl deprotonation bonding to forme GO/SiO2 nanosheet. After all, the composite photocatalyst ZnO/GO/SiO2 was formed by loading the ZnO nanorods on the GO/SiO2 surface via the hydrothermal synthesis. Meanwhile, the photocatalytic Fenton-like system was constructed with H2O2 and ZnO/GO/SiO2. The property and mechanism of the photocatalytic Fenton-like oxidative degradation of methylene blue (MB) was characterized in detail. The results indicating that the photocatalyst can promote the degradation efficiently, with the photogenerated electron replacing the metal ions as activator for H2O2. On account of the property of adsorption and photogenerated electron transfer, the coal-based GO/SiO2 as carrier of ZnO immensely increased the production of active radicals from H2O2, resulting in the promotion of oxidative degradation.