The effect of ambient humidity on the electrical properties of graphene oxide films

Yao Yao,Xiaoyu Li,Xiangdong Chen,Baoqing Zeng,Zuquan Wu,Jinfeng Zhu

doi:10.1186/1556-276x-7-363

Abstract

We investigate the effect of water adsorption on the electrical properties of graphene oxide (GO) films using the direct current (DC) measurement and alternating current (AC) complex impedance spectroscopy. GO suspension synthesized by a modified Hummer's method is deposited on Au interdigitated electrodes. The strong electrical interaction of water molecules with GO films was observed through electrical characterizations. The DC measurement results show that the electrical properties of GO films are humidity- and applied voltage amplitude-dependent. The AC complex impedance spectroscopy method is used to analyze the mechanism of electrical interaction between water molecules and GO films in detail. At low humidity, GO films exhibit poor conductivity and can be seen as an insulator. However, at high humidity, the conductivity of GO films increases due to the enhancement of ion conduction. Our systematic research on this effect provides the fundamental supports for the development of graphene devices originating from solution-processed graphene oxide.

Highlights

Graphene oxide (GO), a single thin sheet of graphite oxide that conventionally serves as a precursor material for preparing graphene [1,2,3], has received increasing attentions in the application of optoelectronic [4,5] and sensor devices [6] due to its inherent electrical and mechanical properties
We used the direct current (DC) measurement and alternating current (AC) complex impedance spectroscopy methods to investigate the effect of ambient humidity on the electrical properties of GO films
The strong interaction of water molecules with GO films was observed through electrical characterizations

Summary

Introduction

Graphene oxide (GO), a single thin sheet of graphite oxide that conventionally serves as a precursor material for preparing graphene [1,2,3], has received increasing attentions in the application of optoelectronic [4,5] and sensor devices [6] due to its inherent electrical and mechanical properties. It is well known that the electrical properties of GO would be influenced by some external stimulations, including reducibility reagent [11], electric field [12,13,14], In earlier works [7,8], several groups have fabricated pristine thin-film-GO-based field effect transistors and resistive switching memory devices. In these applications, GO acts as a charge transport layer. We use both DC measurement and alternating current (AC) impedance spectroscopy methods to elucidate the effect of ambient humidity on the electrical properties of GO films

Methods

Results

Conclusion