Characterization of the dielectric relaxation for (1−x)Ba(Ti0.8Sn0.2)O3–x(Na0.5Bi0.5)TiO3 (x=0.01x=0.01–0.05) ceramics by impedance spectroscopy

Dielectric properties and impedance spectra of (1−x)Ba(Ti0.8Sn0.2)O3–x(Na0.5Bi0.5)TiO3 ceramics with x=0.01x=0.01–0.05 are investigated. The addition of (Na0.5Bi0.5)TiO3 can bring about significant changes in the dielectric properties of Ba(Ti0.8Sn0.2)O3. Impedance/modulus analyses indicate that several dielectric processes in the system play important roles in the significant dielectric relaxational behaviors, which can be observed from the relaxation time ττ. A transition region between relaxor behavior and dielectric relaxation behavior is observed for x=0.01x=0.01–0.02. Further analysis on the activation energy (Ea)(Ea) of grains proves the existence of a phase transition, which lowers the activation energy of the grains by ∼0.5 eV. However, this transition does not influence EaEa for grain boundaries very considerably.

Research highlights
► The dielectric state of (1−x)Ba(Ti0.8Sn0.2)O3–x(Na0.5Bi0.5)TiO3 (x=0.01x=0.01–0.05) was studied.
► Addition of (Na0.5Bi0.5)TiO3 can bring about significant changes in dielectric properties.
► A transition between relaxor and dielectric relaxation behavior is observed.
► The impedance/modulus, relaxation time, and activation energy support the conclusion.
► Several dielectric processes play important roles in the significant relaxation behaviors.