Low Surface Roughness Graphene Oxide Film Reduced with Aluminum Film Deposited by Magnetron Sputtering

Juncheng Liu,Hong-Zhang Geng,Xuguo Huai,Li-Chao Jing,Tao Wang,Jie Wang,Xiaowei Fan

doi:10.3390/nano11061428

Abstract

Graphene film has wide applications in optoelectronic and photovoltaic devices. A novel and facile method was reported for the reduction of graphene oxide (GO) film by electron transfer and nascent hydrogen produced between aluminum (Al) film deposited by magnetron sputtering and hydrochloric acid (HCl) solution for only 5 min, significantly shorter than by other chemical reduction methods. The thickness of Al film was controlled utilizing a metal detection sensor. The effect of the thickness of Al film and the concentration of HCl solution during the reduction was explored. The optimal thickness of Al film was obtained by UV-Vis spectroscopy and electrical conductivity measurement of reduced GO film. Atomic force microscope images could show the continuous film clearly, which resulted from the overlap of GO flakes, the film had a relatively flat surface morphology, and the surface roughness reduced from 7.68 to 3.13 nm after the Al reduction. The film sheet resistance can be obviously reduced, and it reached 9.38 kΩ/sq with a high transmittance of 80% (at 550 nm). The mechanism of the GO film reduction by electron transfer and nascent hydrogen during the procedure was also proposed and analyzed.

Highlights

Transparency as an example selected from Figure 3b, the absorption peak of the original graphene oxide (GO) film was located at 230 nm, and it gradually redshifted to 268 nm along with the increase in the thickness of Al film (Figure 2b–d) for the reduction
This paper proposes a novel and rapid reduction strategy for fabricating flexible AlrGO films using magnetron sputtering of Al as the reducing mediator in acidic conditions
GO can be reduced by the electron transfer and nascent hydrogen only for 5 min, extensively shorter than by other chemical reduction procedures

Summary

Introduction

Since GO dispersions are suitable to produce films on any substrate [10], TCFs composed of GO or reduced GO sheets (rGO) have been prepared via many techniques, including spray coating [11], transfer printing [12], spin coating [13], electrophoretic deposition [14], rod coating [6], and the Langmuir–Blodgett assembly [15], etc. Among these methods, the rod coating method has been widely used in making solution-processed thin films for mass production in the coating industry

Methods

Results

Conclusion