Conformable and ionic textiles using sheath-core carbon nanotube microyarns for highly sensitive and reliable pressure sensors

In order to exploit large-area and conformable electronic textile (e-textile) pressure sensors that are consistently sensitive to a wide range of pressures, both superior electrical and mechanical properties such as high conductivity and high flexibility are strongly required in individual yarns, but remain unexplored in tactile sensor research. In this report, we demonstrate the first highly sensitive, conformable and reliable ionic textile (i-textile) pressure sensors using sheath-core carbon nanotube (CNT) microyarns encapsulated with ionic thermoplastic polyurethane (i-TPU) dielectrics. The piezocapacitive i-textile pressure sensors that are formed by weaving two distinct sets of microyarns (CNT microyarns and i-TPU/CNT microyarns), were capable of simultaneously detecting subtle pressure and human touch with a high sensitivity of 1 nF kPa(-1) and operational reliability over a wide range of pressure, even under low-voltage. We believe that the conformable i-textile pressure sensors suggested by us will be a promising platform to achieve human-adaptive wearable textronics capable of perceiving health monitoring as well as real-time human motion.