Impact of defect-containing graphene oxide nanosheets on the structural, electrical, and dielectric characteristics of graphene oxide

Abstract

In this work, two graphene oxide (GO) samples were prepared using the Hummers method with graphite (g) and KMnO₄ (g) ratios of 1:3 (GO₃) and 1:6 (GO₆). The effect of oxidation degree on the structural, electrical, and dielectric properties of the GO samples was investigated. The structures of the GO samples were studied using various techniques, including X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDXS). XRD analysis revealed an increase in the interlayer spacing and a decrease in the number of layers of the samples with increasing oxidant content. The two GO samples have giant permittivity values of ~10⁵ in the low-frequency range. The characteristics of the functional groups and defects were clarified in terms of their high permittivity. The AC conductivity of the GO samples obeyed Jonscher’s power law. The AC conductivities of GO₃ and GO₆ were calculated as 0.07 and 0.01 S/m at 1 MHz, respectively. The power exponent s has values in the range 0 < s < 1. In addition, a low loss tangent was observed for GO₆ in the high-frequency range.

KEY WORDS: Jonscher’s power law, AC conductivity, Defect, Permittivity, Loss tangent, Graphene oxide

Bull. Chem. Soc. Ethiop. 2025, 39(12), 2583-2592                                                    

DOI: https://dx.doi.org/10.4314/bcse.v39i12.17