Magnetic carbon nanotubes-based microwave absorbents: Review and perspective

The upgrading of electromagnetic technology has stimulated the rapid development of microwave absorption materials (MAMs). Traditional metal absorbents often suffering from high density, large thickness, low chemical stability, associated with poor impedance matching cannot meet the requirements of modern absorbents for large-scale application. In order to resolve the serious electromagnetic interference problem, it is urgent to develop new light and efficient MAMs. As an important member of carbon materials, carbon nanotubes (CNTs) have attracted intensive attention in solving the increasing electromagnetic pollution problem due to their excellent electrical and thermal conductivity. However, bare CNTs always exhibit poor impedance matching and single loss mechanism, which greatly limit their potential for practical application. In this case, magnetic CNTs-based composites (integrated magnetic materials and CNTs) have achieved significant success in addressing the aforementioned disadvantages. Herein, the recent research processes of magnetic CNT-based composites in microwave absorption field are summarized. The performance to reach a strong absorption intensity and a wide effective absorption bandwidth at a thin thickness is direction for recent MAMs studies. The topical and important research achievements are introduced, with the focus on their preparation methods, microwave absorption behaviors, electromagnetic absorption mechanisms. Furthermore, the prospect of the future development of magnetic CNTs-based MAMs are put forward.