Excellent energy storage performances for BaTiO3-based multilayer capacitors through synergistic high-entropy and superparaelectric relaxor strategy

Dielectric capacitors with high energy storage performances are exceedingly desired for the next-generation advanced high/pulsed power devices that demand miniaturization and integration. However, poor energy-storage density (U-rec) and low efficiency (eta) resulted from the large remanent polarization (P-r) and low breakdown strength (BDS), have been the major challenge for the application of dielectric capacitors. Herein, a high-entropy strategy with superparaelectric relaxor ferroelectrics (SP-RFE) was adopted to achieve extremely low P-r and high BDS in BaTiO3 system, simultaneously. Due to the high BDS similar to 800 kV/cm and low P-r <bold>similar to</bold>0.58 mu C/cm(2), high-entropy SP-RFE (La0.05Ba0.18Sr0.18K0.115Na0.115Ca0.18Bi0.18)TiO3 (LBSKNCBT) MLCCs exhibited high U-rec similar to 6.63 J/cm(3) and excellent eta similar to 96%. What's more, LBSKNCBT MLCCs with high-entropy and SP-RFE characteristic also possess a good temperature and frequency stability. In a word, this work offers an excellent paradigm for achieving good energy-storage properties of BaTiO3-based dielectric capacitors to meet the demanding requirements of advanced energy storage applications. (c) 2024 The Authors. Published by Elsevier B.V. on behalf of The Chinese Ceramic Society.