ABSTRACT
The fabrication of self-powered pressure sensors based on piezoelectric materials requires flexible piezoelectric generators produced with a continuous, large-scale, and environmentally friendly approach. In this study, continuous poly(vinylidene fluoride) (PVDF) sheets with a higher ß-phase content were facilely fabricated by the melt-extrusion-calendering technique and a PVDF-based piezoelectric generator (PEG) was further assembled. Such a PEG exhibits a remarkable piezoelectric output performance. Moreover, it possesses prominent stability even after working for a long time, exhibiting potential applications for real-time monitoring of various human movements (i.e., hopping, running, and walking) and gait. This work not only provides the possibility of continuous and environmentally friendly fabrication of PVDF sheets with remarkable piezoelectric properties but also paves a new promising pathway for powering portable microelectronic applications without any external power supply.
ABSTRACT
With the rapid development of wearable electronics, a multifunctional and flexible strain sensor is urgently required. Even though enormous progress has been achieved in designing high-performance strain sensors, the conflict between high sensitivity and a large workable range still restricts their further advance. Herein, a "point to point" conductive network is proposed to design and fabricate a carbon black/polyaniline nanoparticles/thermoplastic polyurethane film (CPUF). The designed structure renders CPUF composites with a wide sensitive range (up to 680% strain), highly sensitive response with a low detection limit of 0.03% strain, and high gauge factor (GF) of 3030.8, together with good sensing stability, fast response/recovery time (80 ms/95 ms), and good durability even after 10000 stretching/releasing cycles. CPUF composites are assembled as wearable strain sensors with the ability of precisely detecting full-range human motions and organic solvents, showing a potential application in human-machine interaction and environmental monitoring.
