Qu Zhengwei, Wang Yi, Yang Pingan, Zheng Wei, Li Nan, Bai Jingying, Zhang Youwei, Li Kailin, Wang Dashuang, Liu Zhaohui, Yao Kexin, Li Rui, Zhang Yuxin
School of Automation, Chongqing University of Posts and Telecommunications, Chongqing 400065, China.
College of Material Science and Engineering, Chongqing University, Chongqing 400044, China.
Molecules. 2021 Dec 27;27(1):135. doi: 10.3390/molecules27010135.
In this work, spherical flower-shaped composite carbonyl iron powder@MnO (CIP@MnO) with CIP as the core and ultrathin MnO nanosheets as the shell was successfully prepared by a simple redox reaction to improve oxidation resistance and electromagnetic wave absorption properties. The microwave-absorbing properties of CIP@MnO composites with different filling ratios (mass fractions of 20%, 40%, and 60% after mixing with paraffin) were tested and analyzed. The experimental results show that compared with pure CIP, the CIP@MnO composites have smaller minimum reflection loss and a wider effective absorption bandwidth than CIP (RL < -20 dB). The sample filled with 40 wt% has the best comprehensive performance, the minimum reflection loss is -63.87 dB at 6.32 GHz, and the effective absorption bandwidth (RL < -20 dB) reaches 7.28 GHz in the range of 5.92 GHz-9.28 GHz and 11.2 GHz-15.12 GHz, which covers most C and X bands. Such excellent microwave absorption performance of the spherical flower-like CIP@MnO composites is attributed to the combined effect of multiple beneficial components and the electromagnetic attenuation ability generated by the special spherical flower-like structure. Furthermore, this spherical flower-like core-shell shape aids in the creation of discontinuous networks, which improve microwave incidence dispersion, polarize more interfacial charges, and allow electromagnetic wave absorption. In theory, this research could lead to a simple and efficient process for producing spherical flower-shaped CIP@MnO composites with high absorption, a wide band, and oxidation resistance for a wide range of applications.
在本工作中，通过简单的氧化还原反应成功制备了以羰基铁粉（CIP）为核、超薄MnO纳米片为壳的球形花状复合羰基铁粉@MnO（CIP@MnO），以提高其抗氧化性和电磁波吸收性能。测试并分析了不同填充比例（与石蜡混合后质量分数分别为20%、40%和60%）的CIP@MnO复合材料的吸波性能。实验结果表明，与纯CIP相比，CIP@MnO复合材料具有更小的最小反射损耗和比CIP更宽的有效吸收带宽（RL < -20 dB）。填充40 wt%的样品综合性能最佳，在6.32 GHz时最小反射损耗为-63.87 dB，在5.92 GHz - 9.28 GHz和11.2 GHz - 15.12 GHz范围内有效吸收带宽（RL < -20 dB）达到7.28 GHz，覆盖了大部分C和X波段。球形花状CIP@MnO复合材料如此优异的微波吸收性能归因于多种有益成分的协同作用以及特殊球形花状结构产生的电磁衰减能力。此外，这种球形花状核壳结构有助于形成不连续网络，从而改善微波入射分散，使更多界面电荷极化，并实现电磁波吸收。从理论上讲，本研究可能会导致一种简单高效的工艺，用于生产具有高吸收、宽频段和抗氧化性的球形花状CIP@MnO复合材料，以用于广泛的应用。
