Ultrasensitive Wearable Pressure Sensors Assembled by Surface-Patterned Polyolefin Elastomer Nanofiber Membrane Interpenetrated with Silver Nanowires.

Abstract

Wearable pressure sensors with ultrahigh sensitivity and flexibility have garnered tremendous attention because of their abilities to mimic the human somatosensory system and perceive surrounding pressure distribution. Herein, an ultrasensitive pressure sensor was fabricated with surface-patterned nanofibrous membranes (SPNMs) via a facile replica method from available plain-weaved nylon textiles. The SPNMs were composed of internal three-dimensional interpenetrating polyolefin elastomer nanofibers and silver nanowires (Ag NWs). The effects of the geometry of surface patterns and the density of the Ag NW network on the sensing performance of the assembled pressure sensor were systematically investigated. The results indicated that clavate groove-shaped surface patterns improved the sensitivity and a larger groove spacing contributed to higher sensitivities, whereas denser Ag NWs would reduce the sensing performance. The optimal pressure sensor assembled with SPNMs-45 and a Ag NW fraction of 3.8% showed high sensitivity (19.4 kPa-1) below the pressure of 2.76 kPa, a low detection limit (<1.6 Pa), fast response (30 and 42 ms), as well as excellent durability. These outstanding performances demonstrated its promising potential for wearable electronic applications, like detecting the spatial pressure distribution and monitoring human muscle motions.