Synthesis, phase transition and analysis of high temperature AC conductivity of (C2H5NH3)2Cd0.5Cu0.5Cl4 perovskite

Abstract

(C2H5NH3)2Cd0.5Cu0.5Cl4 hybrid compound EACCC (EA3C) is studied by X-ray diffraction patterns, differential scanning calorimetry (DSC), and impedance spectroscopy. The (C2H5NH3)2Cd0.5Cu0.5Cl4 crystallizes at room temperature (300K) in the orthorhombic structure with a space group Pbca. Three phases transition (T1 = 225 K, T2 = 333 K and T3 = 358 K) have been identified by DSC measurements. The impedance spectroscopy measurements were performed in the frequency range of (10–107 Hz) and temperature range of (298–383 K). The frequency dependence of AC conductivity is interpreted in terms of Jonscher's law. The variation of the exponent s as a function of temperature suggested that the conduction mechanism in EA3C compound is governed by two processes: the correlated barrier hopping model (CBH) in phase I and the non-overlapping small polaron tunneling model (NSPT) in phase II and III. The density of localized states N (EF) at the Fermi level and the binding energy Wm were calculated. The temperature dependence of the AC conductivity confirms the observed transitions in the DSC study.