Antiferroelectric-like properties in MgO-modified 0.775Na0.5Bi0.5TiO3-0.225BaSnO3 ceramics for high power energy storage

Antiferroelectric-like 0.775NBT-0.225BSN-x wt%MgO ceramics have been prepared by solid state methods. The second phase of MgO was found in grain boundary surroundings with fine grains, which has been confirmed by EDS mapping and XRD results. Frequency dispersion of x = 0 sample was replaced by diffuse phase transition of MgO-doped samples. Antiferroelectric-like properties were firstly observed in MgO modified ceramics. The evolution of antiferroelectric-like /ferroelectric transitions was demonstrated by I-E curves. With increasing MgO concentration, the BDS and EF-EB gradually increase. The leakage current can be reduced by suitable amount of MgO addition. When the doping content is 5 wt.%, the maximum discharge energy density of 2.13 J/cm3 at an electric field of 215 kV/cm was achieved. Detailed analysis can be found in the study.