Effect of yttrium on microstructure, dielectric, ferroelectric and optical properties of BaZr0.10Ti0.90O3 nanoceramics

Y3+ doped barium zirconium titanate Ba((1-3x/2))Y-x(Zr0.10Ti0.90)O-3 ceramics were synthesized by the solgel method. Single phase compounds were confirmed by X-ray diffraction. Morphological analysis shows that the addition of Y3+ content inhibits the grain growth and remarkably changes the dielectric and ferroelectric properties. The temperature dependence of dielectric constant shows a change due to the material's diffuse phase transition, with a shift of the Curie temperature towards room temperature. High dielectric constant (similar to 7937) with low dielectric loss (similar to 0.05) was found for x=0.01 composition at Curie temperature. The diffusivity parameter was calculated as a function of Y3+ content and diffuseness was found to increase with increasing Y3+ content. The remnant polarization shows a slight increase up to x=0.01 composition and then decreases with increasing Y3+ content. The UV-visible optical absorption spectra show that the band gap increases from 3.71 eV to 3.96 eV with increasing Y3+ content. (C) 2014 Elsevier B.V. All rights reserved.