Pyroelectric Ferroelectric and Resistivity Studies on Samarium Modified Barium Strontium Sodium Niobate Ceramics

Abstract

Barium Strontium Sodium Niobate (Ba1-xSrx)2NaNb5O15 (BSNN) belongs to tungsten bronze ferroelectric morphotrophic phase boundary (MPB) system at x = 0.6, having large spontaneous polarisation, pyroelectric coefficient and low dielectic constant and is expected to be applicable for piezoceramic filter and pyroelectic devices. Present communication illustrates preparative conditions and the influence of Sm2O3 on structure, ferroelectric, dielectric, pyroelectric and resistivity properties at and around MPB. Substitution of Sm2O3 decreased the cell volume and Curie temperature and enhance the room temperature dielectric constant. The pyroelectric coefficient at room temperature has been observed to be in the order of 10-9 C/cm2 0C. The figure of merits FMRV, FMRN and FMRIhave been observed to be higher values of the order 10-14 CM/J, 10-12 CM/J, 10-11 CM/J, respectively on both pure and Sm: BSNN compositions. Resistivity studies indicated a PTCR response in the compositions.


(Botswana Journal of Technology: 2003 12(2): 1-7)