The role of cerium(iii)/yttrium(iii) nitrate hexahydrate salts on electroactive β phase nucleation and dielectric properties of poly(vinylidene fluoride) thin films

Abstract

Electroactive β phase nucleation in cerium/yttrium nitrate hexahydrate salt modified PVDF thin filmsviaformation of hydrogen bonds.

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

“…But for WO 3 $H 2 O NPs modied PVDF thin lms the melting peaks have been shied to higher temperatures ($3.6 C) indicating more polar b crystallization in the NCs and the results are consistent with XRD and FTIR data. 8,10,31 3.2.4. First the melting enthalpies of the samples have been investigated from the thermographs, thereaer the X c has been calculated using eqn (2).…”

“…The WO 3 $H 2 O NPs show negative zeta potential (Fig. 8,10,31,37,[42][43][44][45][46][47] The increase of free amorphous chains in the samples due to increase of the fraction of electroactive b phase nucleation also contribute to the large increase in dielectric strength or dielectric constant of the samples. So, the crystallization of polar b phase occurs on the negatively charged at surfaces of the NPs.…”

“…31,[43][44][45][46] The change of the b phase content (F(b)) in NCs is comparatively small at higher loading of the NPs in polymer matrix (Fig. 1 MHz, the dielectric constant also increased almost linearly with ller concentration up to 7.5 mass% and thereaer becomes almost constant.…”

“…Frequency dependence. 31,[43][44][45][46][47] Due to difference in conductivity or dielectric constant of the NPs and PVDF, when an electric eld is applied on the samples the charge carriers move freely and accumulate at the interface of the NPs and the polymer matrix. 13 represents the dependency of the dielectric properties on the frequency of pure PVDF and NPs modied polymer thin lms.…”

“…At lower frequency the dipoles present in the samples may follow the changes of the direction of applied ac electric eld but with increasing eld strength i.e. 31,37,46,47 Dielectric relaxations have been observed aer reaching a characteristic value of frequency 1/t (t is the relaxation time).…”