Impedance analysis of Pb2Sb3LaTi5O18 ceramic

[摘要] 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 singlephase orthorhombic structure. The dielectric studies revealed the diffuse phase transition and the transition temperature was 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 relaxation. The activation energy was estimated to be 0.634 eV from the temperature variation of d.c. conductivity. The nature of variation of d.c. conductivity with temperature suggested NTCR behaviour.

[学科分类] 材料工程

[关键词] Pb2Sb3LaTi5O18;impedance;phase transition;dielectric constant;orthorhombic structure.