Study On Preparation And Propertity Of Ag@TiO₂/PVDF Composites

In recent years,core@shell nanostructures have been a very attractive topic because of their potential applications in different fields.And metal/oxide nanoparticles with a core-shell structure are of essential importance in theoretical sense and practical application in light of easiness of avoiding agglomeration of metal nanoparticles when transferred from one solution to another.Namely,metal and inorganic materials are welled used in electronic field.With silvernitrate(AgNO₃) and titanium-propoxide as the starting materials and dimethylformamide(DMF) as the reducing agent,Ag@TiO₂ core-shell nanoparticles were successfully fabricated.TEM(Transmission Electron Microscope) observation showed that most particles were 60-120nm in diameter and the shell thickness averaged 6-12nm.XRD(X- Ray Diffraction) and XPS(X-Ray Photoelectron Spectroscopy) indicated that the inner core was metallic silver.At the same time,the thickness of shell can be controlled by adapting the initial content of the TTIP,the most suitable reaction temperature was 95℃.The Ag@TiO₂ core@shell nanoparticles-filled polymer poly(vinlydene fluoride)(PVDF)-based composites(0-3 connectivity) were prepared in order to study the effect of core@shell structure on dielectric permittivity in the Ag@TiO₂/PVDF nanocomposites.The results showed that the shell-layer thickness of the Ag@TiO₂ core@shell nanoparticles played a key role on deciding the final value of dielectric permittivity of the nanocomposites.And the variation of permittivity of the nanocomposites with temperature also depends on the shell-layer thickness of the Ag@TiO₂ core@shell nanoparticles.