Solvent Vapor Annealing and Plasma Treatment Stabilize Silver Nanowire Layers

Abstract

Silver nanowires (AgNW) find use in transparent conductive electrodes withapplications in solar cells, touch screens, and wearables. Unprotected AgNWare prone to atmospheric corrosion and lose conductivity over time. Knownpassivation techniques either require submersion of pre-deposited AgNW inliquid compounds or the modification of AgNW inks prior to deposition,which alters viscosity and complicates deposition. Here, new possibilities forstabilization of pre-deposited AgNW networks without need for submersionare explored. It is demonstrated that AgNW networks can be stabilized eitherby argon or hydrogen plasma treatment or by solvent vapor annealing withethanol, methanol, or ethyl acetate. These treatments yielded stable electricalresistance over at least nine weeks, whereas untreated or thermally annealedAgNW layers quickly lost conductivity. The potential of solvent vaporannealing is further explored by demonstrating a new processing techniquefor stable polymer matrix composites containing AgNW. Co-deposited layersof AgNW with polystyrene microbeads are annealed in ethyl acetate vapor tostabilize the AgNW while at the same time merging polymer beads into aclosed film around the AgNW. The resulting composites maintained stableresistance and transmittance for at least seven weeks.