Structural, double Jonscher response and non-Debye-type relaxor behavior of Ba0.75Sr0.25Ti0.9Zn0.2O3 ceramic

A new perovskite Ba0.75Sr0.25Ti0.9Zn0.2O3 (BSTZO) was synthesized via Molten Salt route. The Rietveld analysis of the X-ray pattern at room temperature indicated a tetragonal structure (P4mm) of the BSTZO ceramic. The conduction process and electrical behavior of the BSTZO ceramic were examined in relation to frequency and temperature. The frequency dependence of conductivity spectra follow double Jonscher law. The latter side was described using a both theoretical conduction models assigned to the Correlated Barrier Hopping model at low temperatures and Non-overlapping Small Polaron Tunneling mechanism at high temperatures. Based on the scaling model, the data merged into a unique master curve, which affirms the validity of the Time -Temperature Superposition Principle. The impedance graph investigations showed that the relaxation in BSTZO is a non-Debye process. The dielectric response confirmed the dominance of the Maxwell-Wagner effect in conduction phenomenon. In addition, the dielectric characteristics exhibited a colossal permittivity, which supports the prospective use of the BSTZO ceramic in electronic devices. In the thermal study, the relaxation processes observed by electrical conductivity, impedance, and modulus are associated with oxygen vacancies.