在原子Fe-N-RGO上整合电气性能和极化损失调制,以提高电磁波吸收率
Kaili Zhang1,2,3, Yuefeng Yan2, Zhen Wang4
1State Key Laboratory of Precision Welding & Joining of Materials and Structures, Harbin Institute of Technology, Harbin, 150001, People's Republic of China.
Nano-micro letters
|October 18, 2024
概括
减少氧化石墨烯的金属兴奋剂通过优化导电性和极化来增强电磁波的吸收. 在Fe-N-RGO中的铁位实现了特殊的反射损失和广泛的吸收带宽,证明了先进材料的新策略.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 物理化学 物理化学
背景情况:
- 有效吸收电磁波 (EMWA) 材料对于技术应用至关重要.
- 石墨烯的特性需要调节以优化EMWA性能,特别是导电损失和极化.
- 将异原子引入石墨烯的结构提供了一种可行的方法来调整其电子特性.
研究的目的:
- 开发用于增强EMWA的金属配降解石墨烯氧化物 (M-N-RGO) 复合材料.
- 为了研究各种单一金属原子 (M = Mn,Fe,Co,Ni,Cu,Zn,Nb,Cd,Sn) 与RGO中的协调的作用.
- 阐明M-N4位点,介电性质和EMWA性能之间的关系.
主要方法:
- 使用N-协调原子辅助策略合成M-N-RGO复合材料.
- 材料属性的表征,包括导电性,极化和微观结构 (XAFS,AFM).
- 电磁波吸收性能评估,包括反射损失 (RL) 和有效吸收带宽 (EAB).
- 密度函数理论 (DFT) 计算,以了解底层机制.
主要成果:
- 在2.0毫米厚度下,Fe-N-RGO表现出优越的EMWA,最小反射损失 (RLmin) 为-74.05dB.
- 有效吸收带宽 (EABmax) 为7.05GHz,在1.89毫米厚度的低填充负荷为1 wt%的情况下,可以实现.
- 金属兴奋剂有效调整导电性和极化,优化介电损失和阻抗匹配.
- DFT和实验分析证实Fe-N4位点充当偏振中心,增强双极,接口和缺陷诱导的偏振.
结论:
- 对于EMWA来说,金属兴奋剂是一种高效的策略,用于调节石墨烯的介电性质.
- Fe-N4活性位点通过极化和导电损失机制显著促进协同能量减弱.
- 这项工作为设计用于电磁干扰屏蔽和吸收应用的先进石墨烯基材料提供了基础.
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