Structural refinement, morphological and electrical properties of BaZrO3:Bi(Zn1/2Ti1/2)O3 lead-free ceramics

In this work, barium zirconate (BaZrO3) ceramics were synthesized by solid state reaction method together with bismuth zinc titanate [Bi(Zn1/2Ti1/2)O-3] and sintered at 1200 degrees C for 5 h. These materials were char-acterized by X-ray diffraction (XRD), Rietveld refinement, Scanning spectroscopic measurements (SEM) and Impedance spectroscopy, in order to produce a novel material lead-free due to environmental concern. XRD measurements with the Rietveld refinement technique confirmed that BaZrO3 ceramics have a perovskite-type cubic structure for all different molar ratio studied. In the higher composition of BaZrO3, the perovskite phase symmetry was refined with a single cubic structural based on BaZrO3 code ICSD-27048. For other compositions it was possible to add a second structure regarding the BaO cubic element, which seems to be a remnant phase in the matrices. Impedance Spectroscopy (IS) measurements revealed that BaZrO3:Bi(Zn1/2Ti1/2)O-3 content increased the materials' conductivity. Two conduction mechanisms occur on the matrices: grain and grain boundaries regarding high and low frequencies, respectively. SEM was carried out and confirmed the density of the ceramic materials. (C) 2021 Elsevier B.V. All rights reserved.