Enhanced Energy Storage Performance and Thermal Stability in Relaxor Ferroelectric Bnkt-Bbn Composite Ceramics

Bi0.5Na0.5TiO3 (BNT)-based relaxor ferroelectrics have captured interest for decades as candidate materials to replace lead-based piezoelectrics because of their environmental friendliness. Due to their high maximum polarization and high power density based on their relaxor activity, research has recently concentrated on their applicability to energy storage. Bismuth layer-structured BaBi2Nb2O9 (BBN) was introduced into the perovskite binary material system 0.78(Bi0.5Na0.5TiO3)-0.22(Bi0.5K0.5TiO3) (BNKT). The addition of BBN improved the relaxor behavior and suppressed grain growth compared with pure BNKT ceramics. Moreover, it steadily increased the breakdown strength. As a result, the energy storage efficiency increased from 32% to 58%. In addition, the thermal stability [[EQUATION]] remained below ~5% in the temperature range from room temperature to 200 °C. Consequently, the findings of this study demonstrated that the introduction of BBN into BNT-based relaxor ferroelectrics is an effective way to improve energy storage performance and high temperature stability.