A P(VDF-TrFE) nanofiber composites based multilayer structured dual-functional flexible sensor for advanced pressure-humidity sensing

As an ideal candidate to imitate the perception of human-skin, multifunctional electronic skin (e-skin) has attracted remarkable attention, which has promising applications in industrial robots, intelligent prosthetics and medical monitoring. Herein, we propose a dual-functional flexible sensor with common electrode for advanced pressure-humidity sensing, which is structured by Poly(vinylidenefluoride-cotrifluoroethylene) nanofiber composites based multilayer films. Benefiting from the common use of the interdigital electrode, the structure and external circuit of the proposed flexible sensor are simplified and the crosstalk could be effectively prevented to realize independent sensing. The flexible sensor not only demonstrates excellent pressure sensing performance including high sensitivity, long stability and fairly good ohmic contact, but also exhibits fast response/recovery time, small hysteresis and outstanding long-term stability in humidity sensing, showing excellent potential applications in real-time monitoring of human physiological information. Additionally, based on its excellent performances, an advanced wearable gesture monitoring system for real-time display and an intelligent safety monitoring system to achieve dual-risk avoidance of contact (pressure) and non-contact (humidity) is realized. This work provides a feasible strategy for designing a high performance dual-functional flexible sensor without interference, and presents a roadmap on constructing practical e-skin system in dynamic detection of gestures and better human-robot collaboration.