Preparation of fluorinated carbon nanotube with heterogenous fluorine pattern and the electromagnetic response
Preparation of fluorinated carbon nanotube with heterogenous fluorine pattern and the electromagnetic response
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DOI：
10.1016/j.apsusc.2023.158347
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发表时间：
2023-08
影响因子：
6.7
通讯作者：
Siyao Chen;Rui Qin;Zhiyu Chen;Junwei Lyu;Yangling Ou;Junning Li;Xiangyang Liu;Yang Liu
中科院分区：
文献类型：
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作者：
Siyao Chen;Rui Qin;Zhiyu Chen;Junwei Lyu;Yangling Ou;Junning Li;Xiangyang Liu;Yang Liu
非均匀界面结构对优化微波吸收材料的微波吸收性能具有重要意义。然而，非均匀界面的简易构造和电磁响应的深入探测是具有挑战性的。本文提出了一种利用F2/N2在单壁碳纳米管（SWCNTs）上直接组装异质界面的方法，并揭示了其电磁效应。通过分子筛制备了具有非均匀聚集氟图案的氟化单壁碳纳米管（M-CNTs-F）。与原始单壁碳纳米管和离散氟图案化样品相比，M-CNTs-F上聚集的氟图案导致更强的极化损耗强度，以及随着氟含量的增加而逐渐延长的弛豫时间（τ）。因此，M-CNTs-F表现出上级MA特性，具有最小的反射损耗（RLmin）和在1.76 mm处为−49 dB和5.6 GHz的有效吸收带（EAB）值，填料含量仅为2 wt%。令人惊讶的是，M-CNT-F也表现出优选的低频MA性能。在此基础上，进一步构建了M-CNTs-F复合泡沫，其RLmin和EAB值分别为−66 dB和10.36 GHz。我们的研究突出了直接MA在构建异质界面方面的优势，并强调了异质结模式在MA修饰中的关键作用。
The heterogeneous interface structures are widely recognized for the favorable impact on optimizing microwave absorption (MA) properties of microwave absorbers. However, the facile construction of heterogeneous interface and deep exploration of the electromagnetic response is challenging. Herein, we presented an approach of direct fluorination utilizing F2/N2to construct heterogenous interface on single walled carbon nanotubes (SWCNTs), and the electromagnetic effect was disclosed. By molecular fluorination, fluorinated SWCNTs with heterogeneously aggregated fluorine pattern (M-CNTs-F) were fabricated. The aggregated fluorine pattern on M-CNTs-F lead to stronger polarization loss strength compared to pristine SWCNTs and the discrete-fluorine pattered sample, as well as gradual prolongation of relaxation time (τ) with increase of fluorine content. Consequently, M-CNTs-F demonstrates superior MA property with minimal reflection loss (RLmin) and effective absorption band (EAB) value of −49 dB and 5.6 GHz at 1.76 mm with filler content only 2 wt%. Surprisingly, M-CNTs-F also exhibit preferable low frequency MA performance. Based on aforementioned foundations, M-CNTs-F were furtherly architected to construct CNT-contained composite foam, achieving RLminand EAB value of −66 dB and 10.36 GHz, respectively. Our study highlights the superiority of direct fluorination in constructing heterogeneous interface, and emphasizes the critical role of heterojunction pattern in MA modification.