Improved Electret Properties of Poly(Vinylidene Fluoride)/Lithium Niobate Nanocomposites for Applications in Air Filters

Abstract

AbstractIn this work, the electret properties of poly(vinylidene fluoride) (PVDF)/lithium niobate (LiNbO3, LN) nanocomposites are systematically studied. The LN nanoparticles are fabricated by hydrothermal synthesis followed by melt‐reaction. Their morphology and crystalline structures are characterized by scanning electron microscopy (SEM) and X‐ray diffraction (XRD). The PVDF/LN nanocomposite films are prepared by solution casting with N,N‐dimethylformamide (DMF) as the solvent or melt molding. The crystalline phases of PVDF in both pure samples and nanocomposites are checked by XRD and Fourier transform infrared spectroscopy (FTIR). The measurements of the dielectric and electret properties show that the LN nanoparticles significantly increase the dielectric permittivity (ε) and the thermally stimulated discharge current (TSDC) of the samples. Such materials have potential applications including for air filters and power generators. A demonstration shows that after the same charging process, the PVDF/LN nanocomposites can absorb larger amount of polystyrene (PS) foam microparticles or micrometer size test dusts than the pure PVDF.