Polycrystalline YFeO3 (YFO) and YFe1−(4/3)xTixO3(YFTO) ceramics were prepared using the powder synthesized from the sol‐gel route. X‐ray diffraction analyses of the polycrystalline ceramics revealed the crystallization of the phase in orthorhombic crystal structure associated with the space group Pnma. The magnetization versus magnetic field hysteresis loops were obtained at room temperature for YFO and YFTO ceramics. The magnetic property changes from weak ferromagnetic in YFO to ferromagnetic in YFTO ceramics. The dielectric constant recorded at room temperature for YFTO ceramics was six times higher than that of YFO, whereas the dielectric loss gets reduced to 0.06 from 0.3 for YFO at 1 kHz. Impedance spectroscopy study carried out on YFO and YFTO ceramics confirmed the existence of non‐Debye‐type relaxation. Observed single semicircle in Z′ vs −Z′′ plot established the incidence of intrinsic (bulk) effect and ruled out any grain boundary or electrode effects. The mechanism for the dielectric relaxation and electrical conduction process observed in YFO and YFTO ceramics was discussed by invoking electric modulus formalisms. Activation energy obtained by ac conductivity study suggested that the conduction process in YFO was linked up with the existence of the polaron and oxygen vacancies, whereas only oxygen vacancies contribute to the conduction process in YFTO ceramics.

Polymer nanocrystal composites were fabricated by embedding polyvinylidene fluoride (PVDF) with K 0.5 Na 0.5 NbO 3 (KNN) nanocrystallites of different volume fraction using the hot-pressing technique. For comparison, PVDF-KNN microcrystal composites of the same compositions were also fabricated which facilitated the studies of the crystallite size (wide range) effect on the dielectric and piezoelectric properties. The structural, morphological, dielectric, and piezoelectric properties of these nano and micro crystal composites were investigated. The incorporation of KNN fillers in PVDF at both nanometer and micron scales above 10 vol% resulted in the formation of polar β-form of PVDF. The room temperature dielectric constant as high as 3273 at 100 Hz was obtained for the PVDF comprising 40 vol% KNN nanocrystallites due to dipole-dipole interactions (as the presence of β-PVDF is prominent), whereas it was only 236 for the PVDF containing the same amount (40 vol%) of micron-sized crystallites of KNN at the same frequency. Various theoretical models were employed to predict the dielectric constants of the PVDF-KNN nano and micro crystal composites. The PVDF comprising 70 vol% micron-sized crystallites of KNN exhibited a d 33 value of 35 pC/N, while the nanocrystal composites of PVDF-KNN did not exhibit any piezoelectric response perhaps due to the unrelieved internal stress within each grain, besides the fact that they have less domain walls.

An organic supramolecular ternary salt (gallic acid: isoniazid: water; GINZH) examined earlier for its proton conducting characteristics is observed to display step like dielectric behaviour across the structural phase transition mediated by loss of water of hydration at 389K. The presence of hydration in the crystal lattice along with proton mobility between acid-base pairs controls the "ferroelectric like" behaviour until the phase transition temperature.Research in development of organic molecular systems as functional materials has been of specific interest in recent times. 1 The simplicity, cheap synthesis, flexibility and non-toxic nature

Nanocrystalline powders of Ba 1 -x Mg x Zr 0.1 Ti 0.9 O 3 (x = 0.025-0.1) were synthesized via citrate assisted sol-gel method. Interestingly, the one with x = 0.05 in the system Ba 1 -xMg x Zr 0.1 Ti 0.9 O 3 exhibited fairly good piezoelectric response aside from the other physical properties. The phase and structural confirmation of synthesized powder was established by X-ray powder diffraction (XRD)

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