Investigation of electrical behavior and dielectric properties in polycristalline Pr0.8Sr0.2MnO3 manganite perovskite

Abstract The electrical and dielectric properties of Pr0.8Sr0.2MnO3 perovskite prepared by the solid-state method were investigated. The complex impedance results showed the contribution of grain and grain boundaries in the conduction mechanism. The dielectric data have confirmed the presence of interfacial polarization in the structure. Moreover, a dielectric transition fitted by Curie-Weiss law was observed. Besides, the observed relaxation diffuse phase transition is attributed to a strong heterogeneity introduced by the substitution of Pr by Sr ions. DC electrical measurements indicate that the structure exhibits a semiconductor behavior and the conductivity is governed by hopping process. The AC conductivity measurements show a clear semiconductor-metallic transition at high temperatures. The AC conductivity data can be divided into two parts, the first of which is a semiconductor one, described by the NSPT model, at low temperatures and the second is a metallic regime, fitted by the classical Drude model, at high temperatures.