Sun He, Yi Shuang-Qin, Li Nan, Zou Kang-Kang, Li Jie, Xu Ling, Wang Yue-Yi, Yan Ding-Xiang, Li Zhong-Ming
College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610065, China.
School of Aeronautics and Astronautics, Sichuan University, Chengdu 610065, China.
J Colloid Interface Sci. 2023 Nov;649:501-509. doi: 10.1016/j.jcis.2023.06.109. Epub 2023 Jun 17.
The impedance matching performance of carbon nanotubes (CNTs) can be effectively enhanced by developing a uniform magnetic impedance matching layer, which can take on critical significance in achieving the desirable microwave absorption (MA) performance. To obtain a uniform coating of Nickel (Ni) nanoparticles on CNTs, several methods have been developed (e.g., the γ-irradiation technique, electroless deposition, as well as microwave welding method). However, the intricate and complicated conditions of the above-mentioned methods limit their wide application. Therefore, controlling the distribution of Ni nanoparticles with the aid of a concise and effective method remains a great challenge. Herein, in view of the uniform dispersion effect of polyvinylpyrrolidone (PVP) on CNTs and its complexation with Ni ions, uniform coating of Ni nanoparticles on CNTs is well developed after it is introduced in the hydrothermal process. The prepared Ni/CNTs composites exhibited excellent MA performance in comparison with those of reported Ni/CNTs composites for the ideal impedance matching performance and microwave attenuation ability. When the filler content was only 15 wt%, the minimum reflection loss (RL) reached -39.5 dB, and the effective bandwidth (EB) with RL < -10 dB reached 5.2 GHz at the thickness of 1.15 mm. A scalable strategy of regulating the distribution of Ni nanoparticles and preparing a lightweight microwave absorber based on CNTs was developed in this study, which can serve as a vital guideline for preparing novel MA composite materials.
通过制备均匀的磁阻抗匹配层，可以有效提高碳纳米管（CNT）的阻抗匹配性能，这对于实现理想的微波吸收（MA）性能具有至关重要的意义。为了在碳纳米管上获得均匀的镍（Ni）纳米颗粒涂层，已经开发了几种方法（例如，γ射线辐照技术、化学沉积以及微波焊接方法）。然而，上述方法复杂的条件限制了它们的广泛应用。因此，借助简洁有效的方法控制镍纳米颗粒的分布仍然是一个巨大的挑战。在此，鉴于聚乙烯吡咯烷酮（PVP）对碳纳米管的均匀分散作用及其与镍离子的络合作用，在水热过程中引入PVP后，成功地在碳纳米管上实现了镍纳米颗粒的均匀涂层。与报道的镍/碳纳米管复合材料相比，所制备的镍/碳纳米管复合材料由于具有理想的阻抗匹配性能和微波衰减能力，表现出优异的微波吸收性能。当填料含量仅为15 wt%时，在厚度为1.15 mm时，最小反射损耗（RL）达到-39.5 dB，RL < -10 dB的有效带宽（EB）达到5.2 GHz。本研究开发了一种调节镍纳米颗粒分布并制备基于碳纳米管的轻质微波吸收体的可扩展策略，可为制备新型微波吸收复合材料提供重要指导。
