Ultrasound-enhanced preparation and photocatalytic properties of graphene-ZnO nanorod composite

Abstract

This paper studies the preparation and photocatalytic properties of graphene- ZnO nanorod composite with ultrasonic treatment. Graphene-ZnO nanorod composite photocatalyst with good structure is prepared after ultrasonic treatment for 30 h at 30 kHz in distilled water-ethanol dispersant using ultra-fine zinc powder. The effects of different proportions of zinc powder and expanded graphite on the photocatalytic properties of the composites are investigated. Besides, the prepared Graphene-ZnO nanorod composite photocatalyst is characterized by X-ray diffraction (XRD), laser Raman spectrometer (Ra-man), field emission scanning electron microscopy (SEM), transmission electron microscopy (TEM), and ultraviolet–visible spectroscopy (UV–Vis). It is found that ZnO nanorods in the composite exhibit a hexagonal wurtzite structure and are uniformly coated on the surface of graphene with a diameter of about 20 nm. The degradation efficiency of the composite materials prepared with different proportions of zinc powder and expanded graphite to methyl orange is quite different. When the zinc powder is 1.0 g, the photocatalytic activity of the composite is better than that with the same amount of zinc oxide nanorods. Results prove that the composite materials prepared with the appropriate proportion of raw materials show good photocatalytic performance, and the composite process is simple because it can be completed only under ultrasonic conditions. It breaks through the limitation of high temperature and high pressure in the traditional preparation process and has important reference significance for the development of zinc oxide composite in the field of catalysis.