Enhanced dielectric permittivity with retaining low loss in poly(vinylidene fluoride) by incorporating with Ag nanoparticles synthesized via hydrothermal method

The dielectric properties of poly(vinylidene fluoride) (PVDF) polymer incorporating with silver (Ag) nanoparticles, which were successfully prepared via a hydrothermal method using Aloe vera plant-extracted solution as surface stabilizer and reducing agent (Ag@Ale-NPs), were investigated. Ag@Ale-NPs/PVDF polymer nanocomposites were prepared by a liquid-phase assisted dispersion and hot-pressing methods. The microstructures of the Ag@Ale-NPs and Ag@Ale-NPs/PVDF nanocomposites were characterized. The modification of the Ag@Ale-NPs surface was confirmed using X-ray photoelectron spectroscopy. Interestingly, by using a filler volume fraction of 0.18, the composite exhibited a high dielectric permittivity of ≈92.5 with very low loss tangent of 0.049 at room temperature and 1 kHz. With further increasing a filler volume fraction to 0.22, a greatly enhanced dielectric permittivity of ≈257.2 was obtained with low loss tangent (tan δ ≈ 0.26). Excellent dielectric properties of the Ag@Ale-NPs/PVDF nanocomposites were described by the interfacial polarization effect and the formation of micro-capacitor in the PVDF polymer matrix.