Flexible Transparent Conductive Films Based on Slot Die Coating Induced Oriented Silver Nanowire Networks

Abstract

Silver nanowires based transparent conductive film (AgNWs TCF) is considered as the best substitute for indium tin oxide (ITO) for flexible optoelectronic devices, yet it is confronted with random network distribution, high junction resistance and poor surface uniformity. Herein, highly aligned bilayer orthogonal AgNWs TCFs were fabricated via a improved slot die coating process compatible with roll-to-roll manufacturing. Appropriate ink rheology and coating parameters allows the controlled alignment of AgNWs, while mutually perpendicular coatings and subsequent mechanical pressing enable the construction of bilayer orthogonal conductive network structure. The resultant bilayer orthogonal AgNWs TCF exhibits excellent optoelectronic performance with a high transmittance of 95.4% at 550 nm and a low sheet resistance of 19 Ω sq⁻ 1 . The surface roughness of bilayer orthogonal AgNWs TCF reaches to 5.92 nm, 46% lower than that of conventional random networks. The shear-induced alignment, controlled drying and mechanical pressing can synergisticly promote nanowire ordering, reduce junction resistance, and improve interlayer electrical contact. This work provides a scalable strategy for fabricating high-performance AgNWs TCFs, and has strong potential application in roll-to-roll production of flexible optoelectronic devices.