Optical and dielectric relaxor behaviour of Ba(Zr_0.25Ti_0.75)O₃ceramic explained by means of distorted clusters

Abstract

In this work, Ba(Zr 0.25 Ti 0.75)O 3 ceramic was prepared by solid-state reaction. This material was characterized by x-ray diffraction and Fourier transform Raman spectroscopy. The temperature dependent dielectric properties were investigated in the frequency range from 1 kHz to 1 MHz. The dielectric measurements indicated a diffuse phase transition. The broadening of the dielectric permittivity in the frequency range as well as its shifting at higher temperatures indicated a relaxor-like behaviour for this material. The diffusivity and the relaxation strength were estimated using the modified Curie-Weiss law. The optical properties were analysed by ultraviolet-visible (UV-vis) absorption spectroscopy and photoluminescence (PL) measurements at room temperature. The UV-vis spectrum indicated that the Ba(Zr 0.25 Ti 0.75)O 3 ceramic has an optical band gap of 2.98 eV. A blue PL emission was observed for this compound when excited with 350 nm wavelength. The polarity as well as the PL property of this material was attributed to the presence of polar [TiO 6 ] distorted clusters into a globally cubic matrix.

Structure and optical properties of [Ba1–xY2x/3](Zr0.25Ti0.75)O3 powders

“…2(a)). According to the literature [40] describes that the structural organization as well as the polarization mechanisms into the cubic BZT structure are related to the presence of polar [ 6 ]. According to the literature [51,52], these Raman-active modes can be divided into longitudinal (LO) and transverse (TO) components, as a consequence of the long-range electrostatic forces responsible for the lattice ionicity.…”

“…Therefore, in this work, we report on the structure and optical properties of [ [40]. In this synthesis method, barium carbonate (BaCO 3 ) (99%, S.D.…”

“…A plausible explanation for this phenomenon has been reasoned in the assumption that the distribution of non-polar [ZrO 6 ] clusters into the lattice reduces the dipolar interactions between the polar [TiO 6 ] clusters [57]. Also, these kinds of clusters are responsible for the A 1 (LO 3 ) mode observed at 718 cm À1 [40].…”

Temperature-stable dielectric properties from −20°C to 430°C in the system BaTiO3–Bi(Mg0.5Zr0.5)O3

“…The distinctive properties of classical relaxor dielectrics are broad, frequency-dependent peaks in plots of relative permittivity ( r ) versus temperature, and strong frequency dispersion in dielectric loss tangent (tan ) [1][2][3][4][5]. Relaxor characteristics were first discovered by…”

Glassy behavior study of dysprosium doped barium zirconium titanate relaxor ferroelectric

“…Present composition BaZr 0.25 Ti 0.75 O 3 is chosen as the host material because it shows relaxor behavior and detailed optical, structural and dielectric studies have been reported by Ref. [22].…”