Hierarchically rough structured and self-powered pressure sensor textile for motion sensing and pulse monitoring.

Nowadays, the real-time human motion sensing and pulse monitoring can provide significant basis for health assessment and medical diagnosis. Nevertheless, it is still a big challenge to design a lightweight, flexible and energy-sustainable pressure sensor with high sensitivity and breathability. Here, we fabricated a triboelectric all-fiber structured pressure sensor via facile electrospinning technique. The constructed sensor textile hold a composite structure made up of PVDF/Ag NWs nanofibrous membrane, EC nanofibrous membrane and two layers of conductive fabrics. This wearable device with high shape adaptability exhibited excellent sensing capability due to the introduced hierarchically rough structure on the nanofibers. The sensitivity can reach up to 1.67 V·kPa-1 and 0.20 V·kPa-1 in the pressure range of 0-3 kPa and 3-32 kPa, respectively. The fabricated sensor textile also showed a superior mechanical stability even after a continuous operation of 7200 working cycles. This sensor textile was easily conformable on different desired body parts for dynamic motion sensing and real-time pulse monitoring. It can work in a self-powered manner to detect and quantify various human motions associated with joints, such as elbows, knees and ankles. Additionally, it can be placed on the carotid artery to capture the pulse signals, serving as a reliable way to reflect the state of health. This work has great possibilities to promote the rapid advancement and broad applications of multifunctional pressure sensors and next-generation wearable electronics.