Impedance analysis of Pb2Sb3LaTi5O18 ceramic

Polycrystalline sample of Pb2Sb3LaTi5O18, a member of tungsten-bronze (TB) family, was prepared using a high temperature solid-state reaction technique. XRD analysis indicated the formation of a single-phase orthorhombic structure. The dielectric studies revealed the diffuse phase transition and the transition temperature found to be at 52 °C. Impedance plots were used as tools to analyse the sample behaviour as a function of frequency. Cole–Cole plots showed Debye-type relaxation. The activation energy was estimated to be 0.634 eV from the temperature variation of dc conductivity. The nature of variation of dc conductivity with temperature suggested NTCR behaviour.