Low-loss ferroelectricity in (Bi, Sn)-modified Na1−xBaxNb1−xTixO3 (x = 12.5%)

Abstract

Na0.875Ba0.125Nb0.875Ti0.125O3 (NNBT) and Na0.875Ba0.11Bi0.01Nb0.875Ti0.11Sn0.0112O3 synthesized by solid-state technique exhibit P4bm symmetry. Dielectric-relaxations for NNBT show a transition to an antiferroelectric state below 449 °C (TC) with a prominent fall in the dielectric constant and the dielectric loss, like parent NaNbO3. Below 175 °C (TF) Ba, Ti-doping induced frequency-independent dielectric peak marks the ferroelectric phase. With 1.5% Bi, Sn-doping in NNBT, the grain size and the density of the ceramic increase. Bi, Sn-doped NNBT exhibits dielectric transitions at TC and a diffused TF but with reduced conductivity. The doped NNBT system presents a high electrostrictive coefficient of ∼0.06 m4/C2.