Enhanced energy storage in tungsten bronze-based ferroelectrics and MLCCs via a multi-coating engineering

Area of Science:

• Materials Science
• Ceramics Engineering
• Electrical Engineering

Background:

• High-power pulsed systems require dielectric capacitors with high energy density and efficiency.
• Perovskite ceramics are widely used but face challenges in balancing performance and fatigue endurance.

Purpose of the Study:

• To develop novel tungsten bronze-based dielectric capacitors with enhanced energy density and efficiency.
• To overcome the limitations of current ceramic capacitors in high-power applications.

Main Methods:

• Incorporation of a Ba_1-xSr_xTiO₃ second phase into a Ba_1-xSr_xNb_2-yTa_yO₆ matrix.
• Chemical coating with a SiO₂ layer and fabrication of multilayer ceramic capacitors.
• Investigating the effects of compositional gradients and dual-core-shell structures on material properties.

Main Results:

• Achieved an energy density of 21.1 J/cm³ and 84.5% efficiency in prepared ceramics.
• Attained a record energy density of 23.2 ± 1.2 J/cm³ and 92.8 ± 0.4% efficiency using multilayer design and thickness effect.
• Demonstrated remarkable stability under varying frequency, temperature, and fatigue conditions.

Conclusions:

• The developed tungsten bronze-based capacitors represent a significant advancement for high-power pulsed systems.
• The unique structural features enhance polarization and breakdown strength, leading to superior performance.
• These findings offer a promising alternative to existing dielectric capacitor technologies.