Electrospun Core–Sheath PVDF Piezoelectric Fiber for Sensing Application

In recent years, piezoelectric polymer sensors are used in energy harvesting and self-powered sensing due to their flexibility, low density, and high piezoelectric constant, and their performances may be improved through a careful architectural design. Herein, we reported a facile strategy for fabricating core-sheath piezoelectric fiber (C-PEF) by directly electrospinning poly(vinylidene fluoride) (PVDF) onto the stainless steel wires. Such C-PEF can well respond to bending deformation with different degrees, and therefore it can be assembled into a piezoelectric bending sensor for airflow speed sensing. Furthermore, spring-like structured C-PEF (S-C-PEF) can serve as a piezoelectric spring sensor and in a sophisticated manner monitor human sleep behavior. This work paves a way for developing multigeometric piezoelectric sensors though a low-cost, facile, and reliable method, showing potential applications including bending sensing and health monitoring.