Microtructure and dielectric properties of (1 − x)Pb(Yb1/2Ta1/2)O3-xPb(Fe1/2Ta1/2)O3, 0 ≤ x ≤ 0.2 solid solution ceramics

Polycrystalline samples of (1 − x)Pb(Yb1/2Ta1/2)O3-xPb(Fe1/2Ta1/2)O3 with x = 0.0, 0.1, 0.13, 0.15, 0.18 and 0.2 are prepared by solid state reaction method. The formation and structural changes are identified by X-ray diffraction studies. A uniform distribution of grains is observed from the microstructure by scanning electron microscopy. The dielectric measurement of the compounds is carried out at 1-200 kHz in the temperature range −100 to 300 °C. The substitution of Fe3+ ion at Yb3+ sites of Pb(Yb1/2Ta1/2)O3 significantly enhances the dielectric constant value, increases the diffuseness in the mode of phase transition and lowers the transition temperature. A detailed analysis of the dielectric response of the compounds is given in conjecture with their structural data.