Enhanced electrostatic energy-storage performances in the high-entropy Bi0.5Na0.5TiO3-based ceramic capacitors

Abstract

As one of the core components in electronic devices, dielectric capacitors with superior electrostatic energy-storage performances have captured great interest recently. In this Letter, the B-site high-entropy end-member Ba(Ti0.2Zr0.2Hf0.2Fe0.2Nb0.2)O3 was introduced into Bi0.5Na0.5TiO3 (BNT) ceramics to improve the entropy configuration. Accordingly, the coexisting PNRs with R3c and P4bm, enhanced dielectric relaxation, and decreased grain size were obtained in entropy modified BNT ceramics, leading to slim ferroelectric hysteresis (P–E) loops with reduced Pr and small hysteresis, as well as promoted electric breakdown strength (Eb). Resultantly, the optimal ceramics presented a high recoverable energy density (Wrec) of 7.1 J/cm3 and a high efficiency (η) of 89.5% under 360 kV/cm, along with excellent frequency (10–100 Hz), cycling (1–106), and temperature (25–160 °C) stability. This work demonstrates the practicability of high-entropy engineering in seeking for high-performance dielectric capacitors for advanced high/pulsed power devices.