Modulating the Effect of Yttrium Doping on the Structural and Dielectric Properties of Barium Titanate

In this paper, the influence of yttrium doping on the structural, dielectric, and piezoelectric properties of Ba1-1.5xYxTiO3 (x=0-0.03) is investigated. The samples are synthesized using solid-state route (SSR). The synthesized materials are analyzed by X-ray diffraction (XRD), which indicated the formation of crystalline materials exhibiting tetragonal phase. The samples with composition x=0.005 and 0.01 are denser relative to other samples. The dielectric constant and loss tangent are measured in the temperature range -30 to 250 degrees C for different frequencies. The dielectric constant increases upto x=0.005 (7555 at 1kHz) and decreases thereafter. The shifts in the transition temperature (T-c) are corroborated with differential scanning calorimetry (DSC) studies. The electron paramagnetic resonance (EPR) data reveals that yttrium occupied Ti-site after a certain limit of dissolution at Ba-site. Modified Curie-Weiss law was employed to study the extent of diffusivity. The effects of Y doping on morphology are investigated using scanning electron microscopy. The maximum remanence value (2P(r)) and piezoelectric coefficient (d(33)) are 8.178Ccm(-2) and 116pC/N respectively for x=0.005 doping composition. A correlated behavior of optimum values is observed in density, dielectric constant, and piezoelectric coefficient which can be exploited for various applications.