Time to failure modeling of silver nanowire transparent conducting electrodes and effects of a reduced graphene oxide over layer

Abstract

Transparent conducting electrodes (TCE) with increased robustness and stability were produced from a composite of silver nanowires (AgNW) and reduced graphene oxide (GO) using ultrasonic spray coating. Ultrasonic spray coating is suited for large area depositions and thin films of AgNW and reduced GO TCEs with consistent optoelectronic properties were produced using this method and the reduction of GO was kept environmentally friendly by using ascorbic acid (AA) as the reducing agent. TCEs produced in this manner were highly conductive and had an average sheet resistance of 5.3Ω/□ and an average transmittance of 64.9% ― the best TCE produced in this manner had a figure of merit of 190. Here, AgNWs were protected from humidity induced degradation and the effect of capillary instability at elevated temperatures on the nanowires was retarded by the introduction of a GO–AA over layer. A τ value of 1.5×10−9 was found to signify the onset of capillary instability induced failure in the AgNW TCE and from experimentally supported calculations, it was predicted that the lifetimes of nanowire TCEs under thermal degradation could be extended significantly by keeping the gaseous environment oxygen free.