Yolk-shelled Co@SiO2@Mesoporous carbon microspheres: Construction of multiple heterogeneous interfaces for wide-bandwidth microwave absorption.
Yolk-shelled Co@SiO2@Mesoporous carbon microspheres: Construction of multiple heterogeneous interfaces for wide-bandwidth microwave absorption.
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DOI：
10.1016/j.jcis.2021.09.028
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发表时间：
2021-09
影响因子：
9.9
通讯作者：
Baolei Wang;Yonggang Fu;Jing Li;Tongshen Liu
中科院分区：
文献类型：
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作者：
Baolei Wang;Yonggang Fu;Jing Li;Tongshen Liu
目前，在微波吸收的实际应用中，开发单一厚度下宽带带宽的微波吸收体仍然是紧迫和具有挑战性的。构建多组分、多结构的复合材料是获得增强微波吸收性能的有效策略。本文通过原位罐合成、碳化还原和后续蚀刻制备了蛋黄壳Co@SiO2@介孔碳（Co@SiO2@MC）微球。通过控制SiO2的刻蚀，同时获得介孔碳壳和空腔结构。介孔壳和内部空隙中的大碳-空气界面延长了电磁波的传播路径并增强了散射。由于强介电/磁损耗、不同成分和微结构之间的协同效应以及优异的阻抗匹配，Co@SiO2@MC微球表现出良好的微波吸收性能。值得注意的是，对于介孔碳壳厚度为25 nm的样品，有效吸收带宽（反射损耗低于-10 dB）高达9.6 GHz（8.4-18 GHz），完全覆盖3.7 mm处的整个X和Ku波段。蛋黄壳Co@SiO2@MC微球的超宽吸收带宽凸显了其在微波吸收领域的潜在应用。此外，这项工作为多组分/多结构微波吸收体的制备提供了新的见解。
Nowadays, in the practical application of microwave absorption, it is still urgent and challenging to develop the microwave absorber with broadened bandwidth at a single thickness. Constructing composites with multi-component and multi-structure has been an effective strategy to obtain enhanced microwave absorption performance. Herein, yolk-shelled Co@SiO2@Mesoporous carbon (Co@SiO2@MC) microspheres were prepared by in-situone-pot synthesis, carbonization reduction, and subsequent etching. The mesoporous carbon shell and hollow cavity structure were obtained simultaneously by controlling the etching of SiO2. The large carbon-air interface in the mesoporous shell and interior voids extend the propagation path of electromagnetic wave and enhance scattering. Owing to strong dielectric/magnetic loss, synergistic effect between different components and microstructures, as well as excellent impedance matching, Co@SiO2@MC microspheres exhibit desirable microwave absorption performance. Notably, for the sample with mesoporous carbon shell thickness of 25 nm, the effective absorption bandwidth (reflection loss below −10 dB) is as wide as 9.6 GHz (8.4–18 GHz), completely covering the whole X and Ku bands at 3.7 mm. The ultra-wide absorption bandwidth of the yolk-shelled Co@SiO2@MC microspheres highlight their potential application in the field of microwave absorption. Furthermore, this work provides new insights for the preparation of multi-component/multi-structure microwave absorbers.