Zhou Xinfeng, Jia Zirui, Feng Ailing, Qu Shaolei, Wang Xinao, Liu Xuehua, Wang Bingbing, Wu Guanglei
Institute of Materials for Energy and Environment, State Key Laboratory of Bio-fibers and Eco-textiles, College of Materials Science and Engineering, Qingdao University, Qingdao 266071, PR China.
Institute of Physics & Optoelectronics Technology, Baoji University of Arts and Sciences, Baoji 721016, PR China.
J Colloid Interface Sci. 2020 Sep 1;575:130-139. doi: 10.1016/j.jcis.2020.04.099. Epub 2020 Apr 24.
A series of NiCo/CoNiO@C hybrid composites were successfully prepared by a hydrothermal method and subsequent heat-treatment process. Porous carbon was synthesized through a fabric carbonization process derived from fish skin. The micro-morphology and minor component of NiCo/CoNiO@C hybrid composites could be tuned by controlling the adjunction amount of Co and Ni. The NiCo/CoNiO@C hybrid composite exhibited strong electromagnetic wave absorption performance when the adjunction amount of Co and Ni was 0.4 mmol and 0.2 mmol. The optimal reflection loss could up to -74.3 dB at the matching thickness of 3.8 mm, while the corresponding widest effective absorption bandwidth (reflection loss values lower than -10 dB) is up to 6.32 GHz covering from 11.78 GHz to 18.0 GHz at the matching thickness of 2.4 mm. Based on the Maxwell-Garnet theory, the pore size of porous carbon materials could influence the dielectric constant which has a great effect on impedance. Previous work has illustrated that porous carbon carbonized at 650 °C processes the proper pore size for excellent impedance matching. Besides, NiCo alloy nanosphere and CoNiO nanoflower would provide magnetic loss and interface polarization for attenuating electromagnetic wave energy. Moreover, the conductive loss derived from porous carbon and dipolar loss which originated from the defects are also beneficial to decay electromagnetic energy. This work indicates that the as-prepared NiCo/CoNiO@C hybrid composites accompanied with excellent electromagnetic wave absorption performance could act as a promising absorber to deal with the increasingly serious electromagnetic pollution.
通过水热法和后续热处理工艺成功制备了一系列NiCo/CoNiO@C杂化复合材料。多孔碳是通过鱼皮衍生的织物碳化过程合成的。通过控制Co和Ni的添加量，可以调节NiCo/CoNiO@C杂化复合材料的微观形貌和次要成分。当Co和Ni的添加量分别为0.4 mmol和0.2 mmol时，NiCo/CoNiO@C杂化复合材料表现出很强的电磁波吸收性能。在匹配厚度为3.8 mm时，最佳反射损耗可达-74.3 dB，而在匹配厚度为2.4 mm时，相应的最宽有效吸收带宽（反射损耗值低于-10 dB）可达6.32 GHz，覆盖范围为11.78 GHz至18.0 GHz。基于麦克斯韦-加尼特理论，多孔碳材料的孔径会影响介电常数，而介电常数对阻抗有很大影响。先前的工作表明，在650℃碳化的多孔碳具有合适的孔径，以实现优异的阻抗匹配。此外，NiCo合金纳米球和CoNiO纳米花将提供磁损耗和界面极化，以衰减电磁波能量。此外，多孔碳产生的传导损耗和源自缺陷的偶极损耗也有利于衰减电磁能量。这项工作表明，所制备的具有优异电磁波吸收性能的NiCo/CoNiO@C杂化复合材料可以作为一种有前途的吸收剂，以应对日益严重的电磁污染。
