Rapid-Response and Highly Sensitive Piezocapacitive Pressure Sensor Based on Micro Buckling Periodic Layers for Wearable Applications

Flexible piezocapacitive pressure sensors are prospective candidates for crucial sensing components in wearable human health applications. Despite the low-cost manufacturing of piezocapacitive sensors, high sensitivity and fast response remain tough issues. Herein, a rapid-response and highly sensitive piezocapacitive pressure sensor is developed through a low-cost and scalable solution approach. The sensor is constructed from a silver nanowires (AgNWs)-coated wrinkled polydimethylsiloxane (PDMS) electrode and a pyramid PDMS dielectric layer coated with AgNWs on the flat side. The fabricated sensor exhibits a high sensitivity of 7.88 kPa –1, a rapid response time (10 ms), a fast recovery time (20 ms), and excellent cycling stability (more than 5000 cycles). The sensor has been successfully applied to detecting the touching behavior and joint motion. The monitoring of wrist pulse and fingertip pulse waveforms further shows great potential in human health monitoring and wearable intelligent health systems.