Mediating the Confliction of Energy Storage Performance and Transparency in KNN-Based Ceramics via Synergistic...

Area of Science:

• Materials Science
• Solid State Physics
• Ceramics Engineering

Background:

• Transparent ferroelectrics are crucial multifunctional materials, but achieving high transparency and ferroelectric properties simultaneously is challenging due to crystal structure requirements.
• The coexistence of optical transparency and energy storage in ferroelectric ceramics is hindered by the trade-off between high transmittance crystal structures and ferroelectric polarization.

Purpose of the Study:

• To collaboratively enhance optical transparency and energy storage performance in (1-x)(K0.5Na0.5)0.985La0.015NbO6-xSrZrO3 (KNLN-xSZ) ceramics.
• To investigate the effects of modulating phase structure, domain structure, and grain size on the properties of KNLN-xSZ ceramics.
• To overcome the inherent contradiction between optical transparency and energy storage in KNN-based ferroelectrics.

Main Methods:

• Synthesized KNLN-xSZ ceramics with varying SrZrO3 content (x).
• Utilized phase structure modulation, domain structure refinement (nanodomains), and grain size reduction.
• Characterized optical transmittance, dielectric properties, and energy storage performance (breakdown field, energy storage density, efficiency).

Main Results:

• Established rhombohedral (R) and tetragonal (T) phase boundaries, stabilizing dielectric constants across a wide temperature range (-90 to 270 °C).
• Disrupted long-range ferroelectric ordering, creating active nanodomains that improved relaxor behavior and elongated P-E loops.
• Achieved remarkable optical transparency (up to ~55% in the near-infrared) and excellent energy storage (Wrec = 4.06 J/cm³, η = 75%) in KNLN-0.15SrZrO3 ceramic due to reduced grain size and enhanced breakdown field.

Conclusions:

• Synergistic optimization of phase structure, domain structure, and grain size effectively balances optical transparency and energy storage in KNLN-xSZ ceramics.
• The developed KNLN-0.15SrZrO3 ceramic demonstrates significant potential for multifunctional applications requiring both transparency and energy storage.
• This research provides a robust strategy for modulating KNN-based multifunctional ceramics, alleviating the trade-off between transparency and energy storage.