Yu Wentao, Min Yonggang, Fang Jiyong, Lu Xiaochuang, Wang Ziqing, Jian Lingfeng
School of Materials and Energy, Guangdong University of Technology Guangzhou 510006 China
RSC Adv. 2022 Oct 12;12(45):29070-29077. doi: 10.1039/d2ra04653a. eCollection 2022 Oct 11.
A simple method that combines liquid-liquid phase separation and high-temperature pyrolysis has been developed for the synthesis of polyimide-derived porous carbon/Co particle-based composite absorbers (PIC/Co-800 and PIC/Co-1000). The excellent heat resistance of polyimide allows the composite precursor to maintain its porous structure during pyrolysis. According to the results, PIC/Co-800 and PIC/Co-1000 have a coral-like porous structure, which can enhance the impedance matching property and microwave attenuation ability of the synthesized materials. The impedance matching condition and dissipation ability of PIC/Co-800 and PIC/Co-1000 have been enhanced due to the synergistic effect between the carbon-induced dielectric loss and Co nanoparticle-induced magnetic loss. PIC/Co-1000 shows the highest absorption performance with a minimum reflection loss (RL) of -40.22 dB at a thickness of 5.3 mm and an effective absorption bandwidth (EABW, RL ≤ -10 dB) of 4.10 GHz at a thickness of 1.4 mm. With thicknesses in the range of 1.4 mm to 5.3 mm, the minimum RL value of each thickness is lower than -15 dB. Therefore, this work provides a new strategy for the synthesis of promising absorbing materials with outstanding EMW absorption performance.
一种结合液-液相分离和高温热解的简单方法已被开发用于合成聚酰亚胺衍生的多孔碳/钴颗粒基复合吸收剂（PIC/Co-800和PIC/Co-1000）。聚酰亚胺优异的耐热性使复合前驱体在热解过程中保持其多孔结构。结果表明，PIC/Co-800和PIC/Co-1000具有珊瑚状多孔结构，这可以增强合成材料的阻抗匹配性能和微波衰减能力。由于碳诱导的介电损耗和钴纳米颗粒诱导的磁损耗之间的协同效应，PIC/Co-800和PIC/Co-1000的阻抗匹配条件和耗散能力得到了增强。PIC/Co-1000表现出最高的吸收性能，在厚度为5.3 mm时最小反射损耗（RL）为-40.22 dB，在厚度为1.4 mm时有效吸收带宽（EABW，RL≤-10 dB）为4.10 GHz。在1.4 mm至5.3 mm的厚度范围内，每个厚度的最小RL值均低于-15 dB。因此，这项工作为合成具有优异电磁微波吸收性能的有前途的吸收材料提供了一种新策略。
