| Summary: | In this work, BaTiO3 and Ba(MgxZr0.15Ti0.85-x)O3, (x = 0.005, 0.015, 0.025) ceramics were fabricated by a solid-state sintering route. All of the samples derived a single tetragonal perovskite structure. No significant impurity phases were indicated. A grain growth retardation phenomenon was observed. BaMg0.015Zr0.15Ti0.835O3 ceramics exhibited a maximum dielectric constant of 2010.18 at 102 Hz, showing a strong dependency on crystallite size (36.79 nm). The conductivity of the specimens was mainly due to polaron hopping, while the exponential conductivity factor ranged from 0.96123 to 1.00000. BaMg0.005Zr0.15Ti0.845O3 ceramics showed the lowest electrical resistivity (1.09 Ω-m at 102 Hz) due to its maximum grain size (873.72 nm). Although the complex impedance spectra was a straight line for BaTiO3 ceramics, it became a semicircle for Ba(MgxZr0.15Ti0.85-x)O3 ceramics exhibiting the presence of equal resistance into the grains and grain boundaries. The maximum remnant polarization (44.04 μC/cm2 for loop-5) with a coercive field of 1.67 kV/cm was observed into BaMg0.015Zr0.15Ti0.835O3 ceramics. The obtained optical band gap energy for BaTiO3 was 3.12 eV while the value for BaMg0.005Zr0.15Ti0.845O3, BaMg0.015Zr0.15Ti0.835O3, and BaMg0.025Zr0.15Ti0.825O3 ceramics were 3.10 eV, 3.06 eV and 3.23 eV respectively. Although BaMg0.015Zr0.15Ti0.835O3 ceramics demonstrated the extraordinary electrical and optical properties, the obtained results in BaMg0.005Zr0.15Ti0.845O3 specimens were satisfactory.
|
|---|
