A kirigami concept for transparent and stretchable nanofiber networks-based conductors and UV photodetectors

To meet the increasing demand for wearable electronics today, fabrication of the stretchable devices becomes crucial. In this respect, a stretchable conductor is an essential component for achieving stretchability of the device. Herein, a stretchable and transparent conductor unit, Au-metallized PVP (Au@PVP) nanofiber network on a kirigami-structured PDMS substrate, was newly developed. By a series of comparative studies, the effectiveness of our strategies to the invariant electrical conductivity and high stretchability is convincingly demonstrated. Our stretchable conductor showed high stretchability of 110% without significant change in resistance, similar to 50% increase. It also exhibited similar to 80% transparency, as well as excellent durability. To point out its applicability, we fabricated a transparent and stretchable photodetector having the same geometry. ZnO nanorod, the 1D transparent metal oxide nanostructure, is used as a sensing material owing to its high sensitivity for UV light and large surface to volume ratio. The resulting device showed outstanding on/off ratio of 1020 at its original state and 440 under 80% strain. Its fast response/reset time, high transparency and stable performance indicate the feasibility of the stretchable and transparent optoelectronic device. (C) 2019 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.