Carbon nanotubes with encapsulated Co nanospheres (Co@CNTs) were prepared via a simple approach that exhibits promising control over the morphology and size distribution. The individual CNTs interweave with each other and form a three-dimensional network structure. Test results indicate that the presence of polarized interfaces between the Co spheres and CNTs, as well as an excellent impedance match, leads to a superior performance in electromagnetic wave absorption. A maximum reflection loss of −70.8 dB at 6.24 GHz is obtained for a paraffin containing a 30 wt% Co@CNT inclusion. In addition, the effective absorption bandwidth (with a reflection loss below −10 dB) is 12.95–17.7 GHz at a thickness of 1.9 mm, covering most Ku bands. In particular, such Co@CNT structures demonstrate superior and sustainable electromagnetic wave-absorption properties even in contact with concentrated acid or base, owing to their specific encapsulated structure. These findings could provide new guidelines for the preparation and employment of promising microwave absorption materials that can work under harsh environments through a simple and feasible strategy.

中文翻译：

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具有封装的Co纳米球的CNT的合理设计，可作为优异的耐酸和耐碱微波吸收剂†

制备碳纳米管与封装有限公司纳米球（联合@碳纳米管）通过一种显示出对形态和尺寸分布有希望的控制的简单方法。各个CNT彼此交织并形成三维网络结构。测试结果表明，Co球和CNT之间存在极化界面，以及出色的阻抗匹配，在电磁波吸收方面具有出色的性能。对于包含30 wt％Co @ CNT夹杂物的石蜡，在6.24 GHz处获得的最大反射损耗为-70.8 dB。此外，在1.9 mm的厚度下，有效吸收带宽（反射损耗低于-10 dB）为12.95-17.7 GHz，覆盖了大多数Ku频段。尤其是，此类Co @ CNT结构即使在与浓酸或碱接触时也表现出优异且可持续的电磁波吸收性能，由于其特定的封装结构。这些发现可以为通过简单可行的策略在恶劣环境下工作的有希望的微波吸收材料的制备和使用提供新的指导。