Study of non-centrosymmetric to centrosymmetric structural transformation in Zr-doped Barium Titanate

Non-centrosymmetric to centrosymmetric structural transformation of BaZrxTi1-xO3 (x = 0, 0.05, 0.1, 0.3) as prepared by soilid state reaction was investigated from X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), pair distribution function (PDF) and Raman spectra. Tetragonal BaTiO3 transformed to orthorhombic phase for lower Zr concentration (x = 0.05) and changed to tetragonal to cubic with increasing Zr concentration at room temperature. Dielectric constant changed with the addition of Zr due to the change in local atomic arrangement and achieved highest value 1444 for mole fraction x = 0.1. Change occurred in the intensity for the first Ti-O pair in the PDF pattern due to the incorporation Zr in barium titanate lattice. An extra shoulder due to addition of Zr for the cubic phase of BZT has appeared at 5.64 angstrom in the PDF pattern. Structural and electrical properties of BZT were influenced by additions of Zr due to the change in local atomic arrangement.