Flexible piezoresistive pressure sensor based on wrinkled layers with fast response for wearable applications

Flexible piezoresistive sensors are promising candidates for vital components of prospective wearable sensing systems in human-centered intelligent applications. Herein, we present a novel flexible piezoresistive pressure sensor based on the structure of silver nanowires (AgNWs) on polydimethylsiloxane (PDMS) with a wrinkled surface. Modifying the PDMS microstructure enables the sensor to obtain different sensitivities and pressure ranges. At the optimal conditions, our sensor exhibits a high sensitivity of 2.588 kPa(-1) and a large pressure range with a very low detectable pressure limit (<1 Pa), which can measure a seed weight of sesame (similar to 2 mg). Furthermore, The elastic microstructure-based piezoresistive sensor also possesses a very fast response time (10 ms), rapid recovery (20 ms), and excellent cycling stability. The real-time pressure detection ability is demonstrated by the touching behavior, the muscle and joint movement and the vocalization recognition, presenting great application potential in human-machine interaction, human motion monitoring and intelligent robotic systems.