Hydrogel-based sustainable and stretchable field-effect transistors

Epidermic electronics utilizing organic polymers and hydrogel show great advantages over the traditional silicon-based system, such as flexibility, affordability, biocompatibility and recyclability. In this study, we systematically investigated the interfacial characteristics, conductivity, and mechanical stability of the constituent materials in hydrogel-based stretchable field-effect transistor devices. The crosslinked poly(vinyl alcohol) (PVA)/poly(methacrylic acid) (PMAA) hydrogel was served as the device substrate and insulating dielectric; while the conductive polymer blends of poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS)/PVA were used as gate electrode and source/drain electrodes. The controllable hygroscopicity of crosslinked hydrogel rendered decent stretchability and processability. Accordingly, the stretchable field-effect transistor device could exhibit mobility retention over 70% at 100% strain and mobility retention more than 80% after 500 cyclic stretching at 30% strain. Additionally, the hydrogel-based device was demonstrated to be recycled and reused for three times as the constituent materials of the stretchable FET devices without sacrificing their mechanical and electronic performance. The present study demonstrated a facile methodology to fabricate a stretchable and sustainable FET with crosslinked hydrogel and conductive polymer blends. ? 2021 Elsevier B.V.