Investigations of dielectric, pyroelectric and electrical properties of Ba5SmTi3Nb7O30 ferroelectric ceramic

The polycrystalline sample of Ba5SmTi3Nb7O30 specimen was prepared by high-temperature solid-state reaction method and studied for their dielectric and electrical properties. X-ray diffraction (XRD) analysis reveals the formation of single-phase compound having orthorhombic crystal structure at room temperature. Microstructural analysis by scanning electron microscope (SEM) shows that the compound has well-defined grains, which are distributed uniformly throughout the sample. Detailed dielectric properties of the compound as a function of frequency and temperature show that the compound undergoes non-relaxor kind of ferroelectric-paraelectric phase transition of diffuse nature. Ferroelectric and pyroelectric studies of the compound have been discussed in this paper. The temperature dependence of ac and dc conductivity of the compound has been investigated. The conductivity study over a wide temperature range suggests that the compound has negative temperature coefficient of resistance (NTCR) behaviour. (C) 2009 Elsevier B.V. All rights reserved.