Structure and dielectric studies of (1-x)Ba0.06(Na0.5Bi0.5)0.94TiO3- xBa(Fe0.5Nb0.5)O3 lead-free ceramics

Abstract

In this work, the effects of Ba(Fe0.5Nb0.5)O3 (BFN) addition on the structure and dielectric behaviour of Ba0.06(Na0.5Bi0.5)0.94TiO3 (BNBT) ceramics have been reported. The lead-free (1-x)BNBT-xBFN (where 0 ? x ? 1.0) solid-solutions were synthesized by traditional ceramics fabrication technique and sintered at temperatures up to 1325?C. The X-ray diffraction peaks of the compounds of the entire series were indexed. It is found that the crystal structure of the obtained solid solutions changed from rhombohedral (R3c) to cubic (Pm3m) with an increase in BFN content. The Fourier transformed infrared and Raman spectra also confirmed the formation of solid-solutions. SEMstudies were carried out to evaluate the purity and microstructure of the fabricated ceramics. The dependence of phase transition broadening, phase transition temperature and dielectric parameters with compositional changes were also studied.