BaTiO3–(Na0.5Bi0.5)TiO3 Ceramic Materials Prepared via Multiple Design Strategies with Improved Energy Storage

The investigation of environmentally friendly, Pb-free ceramic dielectric materials with excellent energy storage capability represents a fundamental yet challenging research direction for the development of next-generation high-power capacitors. In this study, linear dielectric Ca0.7La0.2(Mg1/3Nb2/3)O3 was added into [0.65BaTiO3–0.35(Na0.5Bi0.5)TiO3] to form a solid solution. The introduction of Ca0.7La0.2(Mg1/3Nb2/3)O3 modified the crystal structure, enhanced insulation performance and breakdown strength, and reduced hysteresis loss. These improvements collectively contributed to higher energy storage density and efficiency (η). The ceramic pellet with the optimal 10 mol% Ca0.7La0.2(Mg1/3Nb2/3)O3 demonstrated a higher retrievable energy density (~3.40 J cm−3) and efficiency (~81%) at a breakdown strength of 340 kV cm−1 compared to BaTiO3-based ferroelectric ceramics. The sample also exhibited good stability across a temperature range of 30–90 °C and a frequency range of 0.5–300 Hz. Thus, the as-prepared ceramics sample exhibited significant potential for pulsed power device applications.