Ultrahigh energy storage in high-entropy ceramic capacitors with polymorphic relaxor phase

Area of Science:

• Materials Science
• Electrical Engineering
• Solid State Physics

Background:

• Multilayer ceramic capacitors (MLCCs) are essential for high-power-density applications.
• Achieving high energy density and efficiency simultaneously in MLCCs remains a significant challenge.
• Barium titanate (BaTiO3)-based dielectrics are widely used but face limitations in energy storage performance.

Purpose of the Study:

• To introduce a novel high-entropy design strategy for lead-free MLCCs.
• To enhance both energy density and energy efficiency in MLCCs.
• To investigate the impact of high entropy on dielectric properties and device performance.

Main Methods:

• Fabrication of lead-free MLCCs using a high-entropy design based on barium titanate (BaTiO3) with a polymorphic relaxor phase.
• Characterization of material structure, including atomic disorder, lattice distortion, and grain refinement.
• Evaluation of energy storage performance, focusing on energy density, efficiency, and breakdown strength.

Main Results:

• The high-entropy design effectively minimized hysteresis loss by reducing domain-switching barriers.
• Atomic disorder, lattice distortion, and grain refining enhanced the dielectric breakdown strength.
• Achieved a remarkable energy density of 20.8 J/cm³ with an ultrahigh efficiency of 97.5%.

Conclusions:

• The proposed high-entropy design is a promising strategy for developing high-performance MLCCs.
• This approach offers a universal pathway for designing advanced dielectric materials for energy storage.
• The achieved results pave the way for next-generation electronic components with superior energy capabilities.