Negligible energy loss with enhanced thermal stability in NaNbO₃-based multilayer ceramic capacitors via engineered polymorphic nanodomains

Multilayer ceramic capacitors (MLCCs) are essential components in pulsed power systems, requiring optimized bulk ceramics to ensure optimal performance. For this purpose, we choose the NaNbO₃-based antiferroelectric (AFE) ceramics as a promising candidate. Among AFE materials, NaNbO₃ exhibits considerable potential; however, the field-induced metastable ferroelectric (FE) phase at relatively low applied fields results in large hysteresis, which causes high energy dissipation. Antiferroelectric materials are often characterized by the field-induced antiferroelectric-ferroelectric (AFE-FE) phase transition, which remains a significant challenge. Therefore, in this work, we develop inhomogeneous, weakly polar AFE nanodomains through the engineered polymorphic nano-phases, owing to effectively suppressing the AFE-FE phase transition within a wide range of electric fields and temperatures. This strategy is well implemented in the design of highly efficient MLCCs, which display nearly eliminated hysteresis loss. This strategy paves the way for the designing of highly-efficient MLCCs, which would advance their potential for next-generation pulsed power applications.