Improvement of electroactive β phase nucleation and dielectric properties of WO3•H2O nanoparticle loaded poly(vinylidene fluoride) thin films

Tungsten oxide hydrate (WO3 center dot H2O) nanoparticles (NPs) have been prepared by simple hydrazine hydrate reduction. X-ray diffraction, UV-Visible spectroscopy and field emission electron scanning microscopy confirm the formation of phase pure orthorhombic WO3 center dot H2O NPs. Thereafter, poly(vinylidene fluoride) (PVDF) thin films doped with different amounts of WO3 center dot H2O NPs (1-15 mass%) have been prepared via a simple solution-casting method to verify the role of the NPs on the enhancement of electroactive beta phase crystallization and dielectric properties of WO3 center dot H2O NP-PVDF thin films. The interface between the NPs and the polymer matrix takes a vital role in improving b phase nucleation and dielectric properties of the WO3 center dot H2O NP modified PVDF thin films. Strong electrostatic or ion-dipole interaction between the negatively charged NP surfaces and -CH2 dipoles of the polymer matrix at the interface effectively improves the electroactive b phase nucleation and dielectric properties of the nanocomposite thin films.