Lead free dielectric ceramic with stable relative permittivity of 0.90(Na_0.50Bi_0.50Ti)O₃-0.10AgNbO₃

Structural, dielectric and ferroelectric properties in perovskite 0.90(Na0.50Bi0.50Ti)03-0.10AgNb03 polycrystalline powders prepared by sol-gel method are discussed. Diffuse phase transition and new type of dielectric anomaly was observed with highly steady capacitive properties in the 135-450 °C temperature range. This compound shows remarkable dielectric with dielectric constant ε_r ~ 1000 with a variation of ± 7% and tan δ = 0.004~0.25 in 135- 450 °C temperature. In addition, it also showed excellent ferroelectric properties with saturation polarization Ps = 13.5 μC/cm2, remnant polarization of Pr = 7.6 μC/cm2 and a low coercive field Ec = 36 kV/cm at room temperature. Stable dielectric constant (ε_r) and low dielectric loss (tan δ) in a wide temperature range observed for the titled composition makes it an interesting candidate for potential use in fast growing “high-temperature electronics” industry applications.