Photolithographic High‐Conductivity Transparent Conformal rGO/PEDOT:PSS Electrodes for Flexible Skin‐Like All Solution‐Processed Organic Transistors

Abstract

Reduced graphene oxide (rGO) electrodes are known to exhibit high transparency, excellent chemical stability, low‐cost solution processability, and good compatibility for use in solution‐processed organic transistors, but they face fundamental challenges in conductivity and conformability for skin‐like electronics. Here, by inserting a poly(3,4‐ethylenedioxythiophene):poly‐(styrenesulfonate) (PEDOT:PSS) layer, the photolithographic conformal rGO/PEDOT:PSS electrodes with conductivity as high as 2000 S cm−1 can be achieved. Simultaneously, the rGO/PEDOT:PSS hybrid electrodes exhibit high precision down to 1 µm, high transparency of >90% over the visible spectra (400–700 nm), and imperceptible adherence onto damselfly wing without affecting flying. The resulting all‐solution processed organic transistor array presents the enhanced modulation effect of the gate voltage on current, 5.5‐fold increased mobility, and the on‐state current increased by one order of magnitude compared with the neat rGO electrode device, and shows the good adherence to deforming human skins and stable operation on the 10 mm spherical surface with mobility as high as 2.33 cm2 V−1 s−1. The strategy provides a high‐precision, high‐integration, flexible pattern‐designable, and scalable route to produce the high‐conductive transparent conformal rGO/PEDOT:PSS hybrid electrodes for flexible skin‐like all solution‐processed organic transistor array, showing the outstanding potential for future low‐cost soft electronics.