Abstract
Multilayer ceramic capacitors are cornerstone components of modern electronic systems. Yet ensuring reliability under demanding operational conditions, such as elevated temperatures and prolonged cycling, while achieving holistic optimization of recoverable energy density and efficiency remains a significant challenge. Herein, we implement a polar glass state strategy that catalyzes a profound enhancement in energy storage performance by modulating dynamic and thermodynamic processes. This approach minimizes hysteresis loss and improves breakdown strength through hierarchical structural engineering, disrupting nano-domains and refining grains. An ultra-high recoverable energy density of 22.92 J cm(-3) and exceptional efficiency of 97.1%, accompanied with state-of-the-art high-temperature stability are achieved in Bi(0.5)Na(0.5)TiO(3)-based multilayer ceramic capacitors. This strategy promises to be a transformative blueprint for developing cutting-edge dielectric capacitors for high-temperature applications.