PVDF/6H-SiC composite fiber films with enhanced piezoelectric performance by interfacial engineering for diversified applications

Abstract

Piezoelectric silicon carbide (SiC) has been quite attractive due to its superior chemical and physical properties as well as wide potential applications. However, the inherent brittleness and unsatisfactory piezoelectric response of piezoelectric semiconductors remain the major obstacles to their diversified applications. Here, flexible multifunctional PVDF/6H-SiC composite fiber films are fabricated and utilized to assemble both piezoelectric nanogenerators (PENGs) and stress/temperature/light sensors. The open circuit voltage (Voc) and the density of short circuit current (Isc) of the PENG based on the PVDF/5 wt% 6H-SiC composite fiber films reach 28.94 V and 0.24 µA cm–2, showing a significant improvement of 240% and 300% compared with that based on the pure PVDF films. The effect of 6H-SiC nanoparticles (NPs) on inducing interfacial polarization and stress concentration in composite fiber films is proved by first-principles calculation and finite element analysis. The stress/temperature/light sensors based on the composite fiber film also show high sensitivity to the corresponding stimuli. This study shows that the PVDF/6H-SiC composite fiber film is a promising candidate for assembling high-performance energy harvesters and diverse sensors.