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Application of a Coupling Agent to Improve the Dielectric Properties of Polymer-Based Nanocomposites
Published on: September 19, 2020
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Polarization-Driven Energy Storage Enhancement in KNN-Based Relaxor Ceramics under Moderate Electric Field
Xuqing Zhang1, Santan Dang1, Yuanhao Wang1
1Key Laboratory for Macromolecular Science of Shaanxi Province, Shaanxi Key Laboratory for Advanced Energy Devices, Shaanxi Engineering Laboratory for Advanced Energy Technology, School of Materials Science and Engineering, Shaanxi Normal University, Xi'an, Shaanxi, 710119, China.
Small (Weinheim an Der Bergstrasse, Germany)
|October 30, 2025
Summary
Researchers developed lead-free dielectric ceramics for high energy storage performance (ESP) under moderate electric fields. This breakthrough offers practical solutions for energy storage capacitors, enhancing device packaging and usability.
Area of Science:
- Materials Science
- Dielectric Ceramics
- Energy Storage
Background:
- Conventional strategies for lead-free dielectric ceramics focus on ultrahigh breakdown electric fields (Eb), limiting practical device applications.
- High energy storage performance (ESP) under moderate Eb is desirable but scarce in K0.5Na0.5NbO3-based ceramics.
Purpose of the Study:
- To explore approaches for achieving high ESP under moderate Eb in lead-free dielectric ceramics.
- To design a strategy for enhancing ionic polarizability and achieving high saturation polarization.
Main Methods:
- Constructing a relaxor state near room temperature.
- Introducing Ca(Mg1/3Ta2/3)O3 into a K0.44La0.02Na0.5NbO3 matrix.
- Utilizing phase-field simulations to analyze grain boundary effects.
Main Results:
- Achieved a high saturation polarization of 61.1 µC cm-2 and ESP of 6.4 J cm-3 under 370 kV cm-1.
- Observed dynamic polar nanoregions in the optimal ceramic composition (x = 0.06).
- Demonstrated a short discharge time (50.8 ns), improved transparency, and mechanical properties.
Conclusions:
- The proposed design strategy successfully enhances ESP under moderate electric fields.
- High density of grain boundaries positively contributes to breakdown strength.
- Offers a practical pathway for developing high-performance energy storage capacitors.
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