Flexible, transparent patterned electrodes based on graphene oxide/silver nanowire nanocomposites fabricated utilizing an accelerated ultraviolet/ozone process to control silver nanowire degradation

Dong Chul Choo,Sang Kyung Bae,Tae Whan Kim

doi:10.1038/s41598-019-41909-4

Abstract

We developed flexible, transparent patterned electrodes, which were fabricated utilizing accelerated ultraviolet/ozone (UV/O3)-treated graphene oxide (GO)/silver nanowire (Ag-NW) nanocomposites via a simple, low-cost pattern process to investigate the feasibility of promising applications in flexible/wearable electronic and optoelectronic devices. The UV/O3 process of the GO/Ag-NW electrode was accelerated by the pre-heat treatment, and the degradation interruption of Ag NWs was removed by the GO treatment. After the deposition of the GO-treated Ag NW electrodes, the sheet resistance of the thermally annealed GO-treated Ag-NW electrodes was significantly increased by using the UV/O3 treatment, resulting in a deterioration of the GO-treated Ag NWs in areas exposed to the UV/O3 treatment. The degradation of the Ag NWs caused by the UV/O3 treatment was confirmed by using the sheet resistances, scanning electron microscopy images, X-ray photoelectron microscopy spectra, and transmittance spectra. While the sheet resistance of the low-density Ag-NW electrode was considerably increased due to the pre-thermal treatment at 90 °C for 10 min, that of the high-density Ag-NW electrode did not vary significantly even after a UV/O3 treatment for a long time. The degradation interference phenomenon caused by the UV/O3 treatment in the high-density Ag NWs could be removed by using a GO treatment, which resulted in the formation of a Ag-NW electrode pattern suitable for promising applications in flexible organic light-emitting devices. The GO treatment decreased the sheet resistance of the Ag-NW electrode and enabled the pattern to be formed by using the UV/O3 treatment. The selective degradation of Ag NWs due to UV/O3 treatment decreased the transparency of the Ag-NW electrode by about 8% and significantly increased its sheet resistance more than 100 times.

Highlights

Flexible electronic devices have been attractive because of interest in potential applications in next-generation intelligent systems[1,2,3]
The sheet resistance of the Ag NWs with the UV/O3 treatment decreased rapidly with increasing thermal treatment temperature above 70 °C, which might be related to a decrease in the contact resistance caused by the melting of the Ag NWs at their points of contact
When the UV/O3 treatment was applied, the sheet resistance was higher at all pre-annealing temperatures, as shown in Fig. 1(a), but the increase in the sheet resistance was largest for the Ag NWs pre-annealed at 90 °C

Summary

Introduction

Flexible electronic devices have been attractive because of interest in potential applications in next-generation intelligent systems[1,2,3]. A laser-patterning method has been extensively used to form Ag-NW patterns on electrodes[21] Even though this method can form fine, high-quality Ag-NW patterns, because the process cost is very high, using this method to produce a large-sized product is difficult. Various patterning methods, such as the transfer of the Ag-NW patterns to a polymer substrate, photolithography, direct patterning, plasma etching, and magnetic printing, have been proposed as ways to overcome this inherent problem[22,23,24,25,26,27,28]. Scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) measurements were performed to investigate the structural properties and the chemical compositions of those electrodes

Methods

Results

Conclusion