调节基于稀土元素sc的MAX相的电子结构,以增强电磁波吸收
Youbing Li1,2,3, Haoshuai Wei1,3, Lu Chen1,3
1Zhejiang Key Laboratory of Data-Driven High-Safety Energy Materials and Applications, Ningbo Key Laboratory of Special Energy Materials and Chemistry, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang 315201, China.
ACS nano
|March 28, 2024
概括
含的MAX相显示了电磁波吸收的巨大潜力. 使用Sc2GaC MAX的结构工程提高了导电性和高温稳定性,从而产生了出色的波衰减性能.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 电磁主义 电磁主义
背景情况:
- MAX相为电磁波吸收提供了金属和陶性能的独特组合,特别是在恶劣的环境中.
- 对MAX相的挑战包括更高的匹配厚度和阻抗不匹配,限制它们的电磁波衰减能力.
- 研究了结构工程,以调整MAX阶段的电子结构以提高性能.
研究的目的:
- 通过将稀土元素Scandium (Sc) 纳入M位子层,合成一种新的三元MAX相,Sc2GaC MAX.
- 为了研究合成的Sc2GaC MAX的电磁波吸收特性.
- 为了评估Sc2GaC MAX在高温下的热稳定性和性能.
主要方法:
- 三元 Sc2GaC MAX 阶段的合成.
- 使用反射损失 (RL) 和有效吸收带宽 (EAB) 进行电磁波吸收的描述.
- 通过高温 (800°C和1400°C) 的氧化和气氛处理进行热稳定性测试.
主要成果:
- 合成的Sc2GaC MAX表现出极好的导电性和高温稳定性.
- 在1.3毫米厚度下实现了-47.7dB的强烈反射损失,有效吸收带宽为5.28GHz.
- 通过X和Ku频段在1.3至2.1毫米厚度范围内的有效吸收电磁波.
- 在高温下保持出色的吸收性能,在800°C氧化后的最低RL值为-28.3dB,在1400°C处理后的最低RL值为-46.1dB.
结论:
- 通过将Sc纳入MAX阶段,结构工程显著提高了电磁波吸收特性.
- 与其他Ga-MAX相相比,Sc2GaC MAX表现出卓越的性能,具有显著的热稳定性.
- 这项研究强调了通过先进的电磁波吸收器的材料设计来控制内在电子结构的潜力.
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