Comparative Study of Dielectric Properties of Rare Earth Ion Doped Ba5RTi3V7O30 (R = Dy, Sm, Gd)

Polycrystalline samples of Ba5RTi3V7O30 (R = Dy, Sm, Gd) are prepared by Mixed Oxide Process. The X-ray diffractograms at room temperature of these compounds show that the compounds have single-phase orthorhombic structure. The microstructures of the samples are studied from SEM micrographs, which show that the grains are non-uniformly distributed over the entire surface of all the samples. In this work the effect of Rare earth ion substitution on the electrical properties of this sample is studied using impedance spectroscopy. The present dielectric ceramics exhibited ferroelectric-paraelectric phase transition at temperatures around 441 and 385 degrees C for Ba5Ti3DyV7O30 and Ba5GdTi3V7O30 respectively where as no phase transition is observed for Ba5Ti3SmV7O30 compound.