Reduced graphene oxide decorated with ZnO microrods for efficient electromagnetic wave absorption performance

Abstract

A composite RGO/ZnO-mrs, which is reduced graphene oxide (RGO) decorated with ZnO microrods (ZnO-mrs), with excellent electromagnetic wave absorbing performance was prepared by a simple mechanical mixing and direct freeze-drying method. The load of ZnO-mrs in this composite is controlled effectively by changing mass ratio of raw materials Zn(Ac)2·2H2O and graphene oxide (GO), then the balance between dielectric loss ability to electromagnetic wave and impedance matching with free space of the absorbing composite RGO/ZnO-mrs prepared can be obtained, and then its high-performance electromagnetic wave absorption ability. When mass ratio of GO to Zn(Ac)2·2H2O is 1:3, composite RGO/ZnO-mrs filled with only 15 wt% exhibits the most significant electromagnetic wave absorption properties, its minimum reflection loss (RLmin) value of − 38.5 dB is obtained at 15.4 GHz and effective absorption bandwidth (EAB) is up to 5.4 GHz (12.6–18 GHz) with a thickness of 2 mm only. The basic electromagnetic wave absorption mechanism of this composite is discussed systematically. All results demonstrate that composite RGO/ZnO-mrs in this study is very promising as a broadband absorption, light weight, especially with a simple and expandable preparing process electromagnetic wave absorber.