High energy and power density achieved in Bi0.5Na0.5TiO3-based relaxor ferroelectric ceramics with excellent thermal stability

摘要

Dielectric materials with large energy storage density and power density has been a sought-after goal. Here, we report new ceramic system (1-x) [0.5(Bi0.5Na0.5)TiO3-0.5SrTiO(3)]-x NaNbO3 exhibiting an excellent energy storage property (W-rec = 2.34 J/cm(3), eta = 74.6%). It is found that NaNbO3 incorporation can not only enhance the breakdown strength but also induce the formation of ergodic relaxation state, both benefitting the energy storage performance. Meanwhile, further research shows that the ceramic has excellent charge and discharge performance with high power density P-D of 58.52 MW/cm(3) and fast discharge speed t(0.9) of 227 ns. Moreover, corresponding energy storage performance shows good cycle stability (1-10,000) and frequency stability (5-200 Hz), while the discharge performance exhibits excellent temperature stability (20-120 degrees C). These aforementioned merits reveal that of the relaxor ferroelectric 0.5BNT-0.5ST-0.03NN ceramic has great potential in practical pulse power dielectric capacitor applications. (C) 2021 Elsevier B.V. All rights reserved.