High-Entropy Chemical Composition Design for Ultrahigh Capacitive Energy Storage

Area of Science:

• Materials Science
• Ceramic Engineering
• Energy Storage

Background:

• Next-generation electronics demand superior energy-storage performance.
• Optimizing energy density and efficiency in lead-free dielectric ceramics is challenging.
• Current lead-free options struggle to balance high energy density and efficiency.

Purpose of the Study:

• To develop a lead-free dielectric ceramic with enhanced energy storage capabilities.
• To overcome the limitations of simultaneous optimization of energy density and efficiency.
• To provide a new material for pulsed power applications.

Main Methods:

• Designed a high-entropy Bi0.32Na0.32Ba0.32La0.04TiO3-NaNbO3 ceramics system.
• Utilized phase-field simulations and strategic chemical composition.
• Investigated the effects of La-donor doping and NaNbO3 addition.

Main Results:

• Achieved ultrahigh energy storage performance: Wrec ≈ 12.4 J cm⁻³ and η ≈ 82.6% at 790 kV cm⁻¹.
• Demonstrated excellent thermal stability with Wrec ≈ 6.2 J cm⁻³ and η ≈ 85.8% ( < 5% variation from 30-150 °C).
• Stabilized multiphase ultrasmall polar nanoregions through local random fields and stresses.

Conclusions:

• The developed high-entropy lead-free ceramic offers significant advancements in energy storage.
• The material shows great promise for next-generation pulsed power applications.
• This work presents a new paradigm for designing high-performance lead-free ceramics.