高密度双原子对联用于高效的电磁波吸收器
Hongsheng Liang1,2, Shengchong Hui2, Limin Zhang2
1Shanghai Key Laboratory of D&A for Metal-Functional Materials, School of Materials Science & Engineering, Tongji University, Shanghai, 201804, P. R. China.
Small (Weinheim an der Bergstrasse, Germany)
|November 28, 2024
概括
具有Ni-Cu对的高密度双原子 (DA) 吸收器显著增强电磁波 (EMW) 吸收. 这一突破实现了广泛的有效吸收带宽和最小的反射损失,为先进的EMW屏蔽材料铺平了道路.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 电磁学 电磁学 电磁学 电磁学
背景情况:
- 双原子 (DA) 为协调工程提供可调节的结构和高原子效率.
- 设计高密度,异质的DA对以改善电磁波 (EMW) 吸收仍然是一个重大挑战.
研究的目的:
- 在富含的碳基板上构建高密度Ni-Cu双原子 (DA) 吸收器.
- 研究合的Ni-Cu DA对对EMW吸收性能的协同效应.
- 通过电荷再分配和极化损失来探索EMW吸收增强背后的机制.
主要方法:
- 高密度Ni-Cu双原子 (DA) 吸收器的精确构造.
- 金属负荷和EMW吸收特性 (有效吸收带宽,反射损失) 的表征.
- 理论计算以阐明电子结构和电荷转移机制.
主要成果:
- 在Ni-Cu DA吸收器中实现了高金属负荷4.74%的重量.
- 将有效吸收带宽 (EAB) 从0扩展到7.8GHz.
- 在3.60毫米时获得了-70.96dB的最小反射损失 (RLmin),实现了>99.99%的能量吸收.
- 证明了富含电子的位点从N转移到Cu,诱导不对称的极化损失.
结论:
- 结合的Ni-Cu DA对的协同效应显著增强了EMW吸收.
- 这项工作提出了一个可行的策略,用于为先进材料准备高密度DA对.
- 在原子水平上精确调整的协调对称性对于优化EMW吸收至关重要.
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