Enhanced energy storage properties of NaNbO3 and SrZrO3 modified Bi0.5Na0.5TiO3 based ceramics

The (0.9-x)[0.92Bi0.5Na0.5TiO3-0.08BaTiO3]-xSrZrO3-0.10NaNbO3 (x = 0, 0.02, 0.04, 0.06, 0.08, 0.10, abbreviated as BNTBT-100xSZ-NN) lead-free ferroelectric ceramics were prepared by conventional solid state reaction method. XRD Rietveld refinement indicates that R3c and P4bm phases coexist in the sample, while P4bm weakly polar phase accounts for a large proportion of 90%. BNT-100xSZ-NN shows broad permittivity peaks in the ɛ′-T curves. Slim P-E ferroelectric hysteresis loops are obtained due to the long range of ferroelectric order broken by the addition of SrZrO3 and NaNbO3 as well as the enhancement of the weakly polar region. The excellent energy storage properties are obtained at the composition of x = 0.08, which has high energy storage density of 0.95 J/cm3 at the electric field of 110 kV/cm and small variation (7%) in the temperature range of 25-175 °C.