Abstract
The development of advanced flexible large-area electronics
such as flexible displays and sensors will thrive on engineered functional ink
formulations for printed electronics where the spontaneous arrangement of
molecules aids the printing processes. Here we report a printable elastic
conductor with a high initial conductivity of 738 S cm−1 and a record high
conductivity of 182 S cm−1 when stretched to 215% strain. The elastic conductor
ink is comprised of Ag flakes, a fluorine rubber and a fluorine surfactant. The
fluorine surfactant constitutes a key component which directs the formation of
surface-localized conductive networks in the printed elastic conductor, leading
to a high conductivity and stretchability. We demonstrate the feasibility of
our inks by fabricating a stretchable organic transistor active matrix on a
rubbery stretchability-gradient substrate with unimpaired functionality when
stretched to 110%, and a wearable electromyogram sensor printed onto a textile
garment.