Efficient Welding of Silver Nanowires embedded in a Poly(vinylidene fluoride) Film for Robust Wearable Electronics

Silver nanowires (AgNWs) are explored as promising transparent electrodes for flexible plastic devices. However, high NW-NW contact resistance and poor adhesion on bare substrates currently preclude AgNWs from use in transparent wearable applications. Here, a highly efficient large-scale strategy of partially burying AgNWs in the surface of poly(vinylidene fluoride) (PVDF) transparent substrates is reported to greatly improve the conductivity and adhesion of the nanowires. The conductivity of AgNWs is doubled when forming the PVDF/AgNWs electrodes, which requires only 10 min and did not need any post-treatment. Due to the high flexibility and abradability of PVDF film, the conductive surface of PVDF/AgNWs electrodes with junctions and parts of the AgNWs embedded in the PVDF film is robust during multiple deformations, adhesion test, and rubbing test. The chemical resistance is also improved because of the chemical stability of PVDF substrate and the conductive structure of the PVDF/AgNWs electrode. It is further shown that the transparent PVDF/AgNWs electrode is robust enough for wearable applications, such as wearable microcircuits, e-skins, and biomechanical energy harvesters. This work is believed to be a potential step toward applications of PVDF/AgNWs electrode in transparent wearable electronics.