Structure, dielectric behaviours, enhanced polarization responses and energy storage properties in (1???x)SrTiO3–xBi(Mg1/2Ti1/2)O3 ceramics

摘要： In this work, ceramics of (1 ? x)SrTiO3–xBi(Mg1/2Ti1/2)O3 (ST–BMT, x = 0.05–0.5) were successfully prepared. A single-phase perovskite structure is formed for all the compositions. The average structure is cubic at room temperature. The Raman analysis suggests that the 5 mol% BMT addition might cause the existence of the local tetragonal distortions at room temperature. All the compositions display a frequency-dependent and highly diffused dielectric anomaly. The BMT addition can effectively shift the freezing temperature (Tf), from ~ 32 K for x = 0.1 up to ~ 240 K for x = 0.5. The compositions with x = 0.4 and 0.5 show a small change in the relative permittivity (Δε′/??′373 K < ± 15% at 1 kHz) and keep low values of the dielectric loss (tanδ < 0.01 for x = 0.01 at 1 kHz) in the temperature range of 373–523 K. The BMT addition induces an enhancement of the polarization maxima. Among the compositions, 0.7ST–0.3BMT shows the optimum energy storage performance (Wrec, 0.78 J/cm3).