Remarkably enhancing dielectric permittivity and suppressing loss of PVDF via incorporating metal nanoparticles decorated glass fibers

Dielectrics with high permittivity and low dielectric loss have so far received considerable attention because of their wide applications in various electronic devices. However, the enhanced permittivity of dielectrics is always accompanied by an increase in loss. In this work, targeting at enhancing the permittivity of poly(vinylidene fluoride) (PVDF) without elevating loss, gold nanoparticles (Au NPs) decorated glass fibers (GF) are incorporated into the PVDF, forming a unique design of Au@GF/PVDF composites. The effects of gold nanoparticle content, calcination temperature, and hot-pressing pressure on the dielectric properties are studied. Interestingly, for the composite with gold sputtering time of 3 min, a remarkable dielectric enhancement of 430% (i.e. from 7.8 to 33.5 at 10 kHz) along with an obvious loss suppression of 56% (i.e. from 0.0353 to 0.0198) are concurrently achieved. It is believed that, the increase in permittivity is mainly attributed to the Maxwell-Wagner-Sillars effect of effective micro-capacitors and cluster polarization of gold nanoparticles while the suppressed loss is originated from the intrinsic low loss of GF and the Coulomb-blockade effect of gold nanoparticles. This work offers a promising strategy to simultaneously enhance the permittivity and suppress the loss of dielectric materials.