Effect of Annealing Temperature on Energy Storage Performance of SrBi3.25La0.75Ti4O15 Thin Films

Dielectric capacitors, characterized by ultra-fast charge/discharge speeds and high power densities, are widely used in modern electronic power systems. However, their low energy density and poor thermal stability limit applications. In this study, SrBi3.25La0.75Ti4O15 (SBLT) ferroelectric thin films were prepared by the sol–gel method. We systematically investigated the effect of annealing temperature on microstructural evolution, electrical properties, and energy storage performance. The SBLT film annealed at 700 °C exhibited optimal performance, achieving a balanced enhancement in polarization and breakdown strength, with an energy storage density of 48.66 J cm−3 and an efficiency of 78%. The material also demonstrated excellent thermal stability (30–175 °C) and frequency stability (0.1–100 kHz). These findings not only validate the potential of SBLT as a next-generation energy storage dielectric but also provide a practical solution for applications in semiconductor technology.