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Valence-Vacancy Coupled Loss Engineering in LaMnO3 Perovskites for Low-Frequency Microwave Absorption
Shuai Lv1, Xiaomeng Wang2, Jiaxun Wang1
1School of Materials Science and Engineering, Harbin Institute of Technology (Weihai), Weihai 264209, P. R. China.
ACS Applied Materials & Interfaces
|May 11, 2026
Summary
This study introduces a novel perovskite material for efficient low-frequency electromagnetic wave absorption. The material demonstrates excellent high-temperature durability and significant radar cross-section reduction.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Electromagnetism
Background:
- Low-frequency electromagnetic wave absorption is crucial for electromagnetic protection.
- Conventional materials face limitations like large skin depth, weak magnetic response, and poor thermal stability.
- Achieving both high absorption efficiency and high-temperature durability is challenging.
Purpose of the Study:
- To develop a novel material for efficient low-frequency electromagnetic wave absorption with high-temperature durability.
- To investigate a charge imbalance-driven Jahn-Teller strategy for material design.
- To explore the potential of single-phase La1-xCaxMnO3 perovskites.
Main Methods:
- Fabrication of single-phase La1-xCaxMnO3 perovskites using a sol-gel method.
- Investigation of ionic-size mismatch, octahedral distortion, and Mn3+/Mn4+ redistribution.
- Analysis of polarization-related dielectric loss and impedance matching.
Main Results:
- Optimized perovskite sample achieved a minimum reflection loss of -40.46 dB at 4.72 GHz.
- An effective absorption bandwidth of 4.40 GHz was obtained.
- Simulations showed a maximum radar cross-section reduction of 30.7 dB·m2, demonstrating scattering suppression.
Conclusions:
- The charge imbalance-driven Jahn-Teller strategy effectively enhances dielectric loss and impedance matching for low-frequency absorption.
- The fabricated La1-xCaxMnO3 perovskites offer a promising solution for thermally robust, low-frequency absorbing coatings.
- This strategy is generalizable to other perovskite oxide systems.
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