A shape-adaptable and highly resilient aerogel assembled by poly(vinylidene fluoride) nanofibers for self-powered sensing

Abstract

Flexible piezoelectric nanogenerators with high power output and superior mechanical stability that can respond to tiny human movements are essential for the development of portable power sources and smart sensors. Herein, a poly(vinylidene fluoride) (PVDF) nanofiber aerogel with a bionic cytoplasmic matrix structure and controllable super-elasticity is constructed by wet electrospinning for self-powered sensing. The PVDF-based aerogel exhibits remarkable elastic resilience with a high compressive stress of 2 MPa at 50% strain. The three-dimensional porous structure and high specific surface area endow the aerogel excellent electrical properties. The corresponding PVPU-NG device has an optimum output of 156 V and 34.9 μA with a power density of 5.5 W m−2, which can illuminate 50 light-emitting diodes. In addition, this PVPU-NG can respond to tiny human movements and convert mechanical energy into electrical energy to power miniature electronics. Specifically, the PVPU-NG can generate peak-to-peak voltages of approximately 1.8 V and 31 V during elbow bending and walking, respectively. As a result, the PVDF-based nanofiber aerogel, which exhibits high compressive strength and improved pressure sensitivity, demonstrates broad application prospects in wearable electronics and portable power sources.