A Transparent, Smooth, Thermally Robust, Conductive Polyimide for Flexible Electronics. (20th November 2015)

• Record Type: Journal Article
• Authors: Spechler, Joshua A.; Koh, Tae‐Wook; Herb, Jake T.; Rand, Barry P.; Arnold, Craig B.
• Is Part Of: Advanced functional materials. Volume 25:Number 48(2015)
• Page Start: 7428
• Page End: 7434
• Publication Date: 2015-11-20
• Subjects: colorless polyimides -- flexible electronics -- organic light‐emitting diodes -- silver nanowires -- transparent conducting electrodes; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adfm.201503342
• Languages: English
• ISSNs: 1616-301X

Abstract

Abstract : In this work, a thermally and mechanically robust, smooth transparent conductor composed of silver nanowires embedded in a colorless polyimide substrate is introduced. The polyimide is exceptionally chemically, mechanically, and thermally stable. While silver nanowire networks tend not to be thermally stable to high temperatures, the addition of a titania coating on the nano­wires dramatically increases their thermal stability. This allows for the polyimide to be thermally imidized at 360 °C with the silver nanowires in place, creating a smooth (<1 nm root mean square roughness), conductive surface. These transparent conducting substrate‐cum‐electrodes exhibit a conductivity ratio figure of merit of 272, significantly outperforming commercially available indium‐tin‐oxide (ITO)‐coated plastics. The conductive polymide is subjected to various mechanical tests and is used as a substrate for a thermally deposited, flexible, organic light‐emitting diode, which shows improved device performance compared to a control device made on ITO coated glass. Abstract : A fully solution processed composite material of a colorless polyimide, titania, and silver nanowires is presented. This material is a new substrate‐cum‐electrode for optoelectronics devices, which exhibits excellent thermal, mechanical, and chemical stability. A green phosphorescent organic light‐emitting diode device fabricated atop this electrode outperforms an indium‐tin‐oxide‐on‐glass substrate‐cum‐electrode control device.