Dielectric nanocomposite with high dielectric permittivity and low dielectric loss

Abstract

Dielectric flexible nanocomposites featuring ferroelectric barium titanate nanoparticles embedded in poly(vinylidene fluoride) (PVDF) matrix were fabricated by a miscible-immiscible coagulation method followed by hot pressing. The SEM images showed good distribution of nanoparticles with very little particle agglomeration. This microstructure was achievable with or without surface functionalization of the nanoparticles and resulted in high dielectric permittivity and low dielectric loss over a wide range of frequency (10 Hz to 1 MHz). Dielectric permittivity of the composite increased as the filler content increased from 0 to 47 vol % with only a small increase in dielectric loss. At a filler content of 47 vol %, the dielectric permittivity can reach 76 at 1 kHz which is more than 10 times higher than the PVDF matrix while the dielectric loss can remain at < 0.1 at 1 kHz. Due to the simplicity of the processing method, reliable dielectric properties and flexibility, this composite may be useful in many electronic applications such as capacitors and flexible high-k dielectrics components.