Enhanced energy storage performance and thermal stability in relaxor ferroelectric BNKT-BBN solid solution ceramics

Abstract

Bi0.5Na0.5TiO3 (BNT)-based relaxor ferroelectrics have attracted considerable interest over the past decades as candidate materials to replace lead-based piezoelectrics because of their environmental friendliness. Moreover, owing to their high maximum polarization and high-power density resulting from their relaxor activity, BNT-based relaxor ferroelectrics have attracted attention as potential candidates for energy storage. Herein, bismuth layer-structured BaBi2Nb2O9 (BBN) was introduced into the perovskite binary material system 0.78(Bi0.5Na0.5TiO3)-0.22(Bi0.5K0.5TiO3) (BNKT). Compared to pure BNKT ceramics, BNKT-BBN exhibited improved relaxor behavior and suppressed grain growth. Moreover, an increase in BBN content increased the breakdown strength. Consequently, the energy storage efficiency increased from 32 % to 58 %. In addition, the thermal stability (ΔWrec/Wrec) remained below ∼5 % in the temperature range from room temperature to 200 °C. 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.