Three-Dimensional\nStretchable and Transparent Conductors\nwith Controllable Strain-Distribution Based on Template-Assisted Transfer\nPrinting

Abstract

Although stretchable\ntransparent conductors, stemmed from the strategies\nof both conductive composite and structural design of nonstretchable\nconductors, have been extensively studied, these conductors either\nsuffer from low stretchability or require a complex fabrication process,\nwhich drastically limits their practical applications. Here, we propose\na novel strategy combining the design of substrates and a simple template-assisted\ntransfer printing process to fabricate three-dimensional (3D) transparent\nconductors. The strategy not only eliminates the complex and costly\nfabrication processes but it also endows conductors with high stretchability\nand long-term stability, thanks to the controllable strain distribution\nas well as the seamless connection between the conductor layer and\nthe substrate. These newly designed 3D conductors achieve a low sheet\nresistance of 1.0 Ω/sq with a high transmittance of above 85%\nand remain stable without obvious resistance change during 1000 stretching-relaxation\ncycles until 60% strain, which are superior to most reported conductors.\nA large-area stretchable heater based on the 3D conductor realizes\nthe temperature fluctuation below 10% even under a large strain, thus\nshowing huge application prospects in the field of wearable healthcare\nelectronics. The simple solution-processed fabrication method and\nhigh performance such as stretchability and low resistance change\nover a large strain range promote the practical applications of these\nnewly designed 3D conductors.