Enhanced energy-storage performance in BNT-based lead-free dielectric ceramics via introducing SrTi0.875Nb0.1O3

Environmentally friendly lead-free ceramics capacitors, with outstanding power density, rapid charging/discharging rate, and superior stability, have been receiving increasing attention of late for their ability to meet the critical requirements of pulsed power devices in low-consumption systems. However, the relatively low energy storage capability must be urgently overcome. Herein, this work reports on lead-free SrTi0.875Nb0.1O3 (STN) replacement of (Bi0.47La0.03Na0.5)(0.94)Ba0.06TiO3 (BLNBT) ferroelectric ceramics with excellent energy storage performance. Improving relaxor behaviour and breakdown strength (E-b), decreasing grain size, and mitigating large polarization difference are conductive to the enhancement of comprehensive energy storage performances. The phase-field simulation methods are further analysized evolution process of electrical tree in the experimental breakdown. In particular, the 0.70BLNBT-0.30STN ceramic exhibit a large discharged energy density of 4.2 J/cm(3) with an efficiency of 89.3% at room temperature under electric field of 380 kV/cm. Additionally, for practical applications, the BLNBT-based ceramics achieve a high power density (similar to 62.3 MW/cm(3)) and fast discharged time (similar to 148.8 ns) over broad temperature range (20-200 degrees C). Therefore, this work can provide a simple and effective guideline paradigm for acquiring high-performance dielectric materials in low-consumption systems operating in a wide range of temperatures and long-term operations. (C) 2022 The Chinese Ceramic Society. Production and hosting by Elsevier B.V.