A Simple Strategy towards Highly Conductive Silver‐Nanowire Inks for Screen‐Printed Flexible Transparent Conductive Films and Wearable Energy‐Storage Devices

Abstract Printable silver‐nanowire (Ag NW) inks with simple formulation, low cost, and high conductivity are developed and screen printed on flexible poly(ethylene terephthalate) substrates. By using ultralong Ag NWs (≈75 µm in length) as the conductor, the screen‐printed Ag NW patterns exhibit exceptional conductivity (up to 8.32 × 10 3 S cm −1 ) and excellent mechanical robustness. Rheological behavior suitable for screen printing is achieved by adjusting the formulation of the inks, which assures neat and smooth screen‐printed lines with resolution as high as 100 µm. Uniform and honeycomb‐structured Ag NW transparent conductive films with superior flexibility and optical transmittance ≈80% are obtained by screen printing the Ag NW inks. Flexible all‐solid‐state supercapacitors based on Ag NW/PEDOT:PSS electrodes reach areal specific capacitance as high as 8.58 mF cm −2 , a value threefold higher than that of pristine PEDOT:PSS electrodes. Moreover, a high flexibility with a bending angle of 180° and long‐term stability with ≈90% capacitance retention over 2500 cycles, is also obtained, manifesting this material's great potential applications for flexible and wearable energy‐storage devices.