Multifunctional BaTiO ₃ ‐(Bi _0.5 Na _0.5 )TiO ₃ ‐based MLCC with high‐energy storage properties and temperature stability

Abstract

Abstract BaTiO 3 ‐(Bi 0.5 Na 0.5 )TiO 3 (BTBNT)‐based multilayer ceramic capacitor (MLCC) chips with the inner electrodes being Ag0.6/Pd0.4 are prepared by a roll‐to‐roll casting method. The BTBNT‐based MLCC chips with ten‐dielectric layers can be sintered very well at a low temperature of 1130°C via two‐step sintering (TSS). X‐ray diffraction (XRD) and transmission electron microscope (TEM) results show that MLCC chips are a core‐shell structure with two phases coexistence. The core exhibits a tetragonal phase at room temperature and then gradually changes into a cubic phase when the temperature increases above T c (175°C). While, the shell exhibits a pseudocubic phase at all tested temperature from 25°C to 500°C. BTBNT‐based MLCC chips exhibit a broad temperature stability and meet the requirement of Electronic Industries Association (EIA) X9R specifications. In terms of energy storage performance, a large discharge energy density of 3.33 J/cm 3 can be obtained at 175°C under the applied electric field of 480 kV/cm. Among all tested temperature ranging from −50°C to 200°C, the energy efficiency of all chips is higher than 80%, even under a high applied electric field. The experimental results indicate that this novel BTBNT‐based X9R MLCCs can be one of the most promising candidates for energy storage applications, especially operated in high temperature.