Synthesis, Microstructure and Dielectric Properties of Zirconium Doped Barium Titanate

摘要

We report on synthesis, microstructural and relaxor ferroelectric properties of Zirconium (Zr) doped Barium Titanate (BT) samples with general formula Ba(Ti_(1-x)Zr_x)O_3 (x=0.20, 0.35). These lead-free ceramics were prepared by solid state reaction route. The phase transition behavior and temperature dependent dielectric properties and composition dependent ferroelectric properties were investigated. XRD analysis at room temperature confirms phase purity of the samples. SEM observations revealed retarded grain growth with increasing Zr mole fraction. Dielectric properties of BZT ceramics is influenced significantly by small addition of Zr mole fraction. With increasing Zr mole fraction, dielectric constant decreases while FWHM and frequency dispersion increases. Polarization vs electric field hysteresis measurements reveal ferroelectric relaxor phase at room temperature. The advantages of such substitution maneuvering towards optimizing ferroelectric properties of BaTiO_3 are discussed.