Hierarchical architecture bioinspired CNTs/CNF electromagnetic wave absorbing materials

Robust and flexible composite aerogel films with porous multilayered structures toward broadband electromagnetic wave absorption

“…Namely, when sample thickness meets the 1/4 model equation mentioned earlier, a large amount of incident and reflected EMWs that are 180° out of phase shift will cancel out at the air-absorber interface. 51 Meanwhile, to further illustrate the relationship between impedance matching and EMW absorption, the plot of Z = | Z in / Z 0 | versus varying frequencies is presented in Fig. 6(o).…”

Electromagnetic Absorption by Magnetic Oxide Nanomaterials: A Review

“…Carbon nanotubes (CNTs) are one-dimensional nanomaterials that possess low background current, wide potential window, high mechanical modulus, good thermal stability, and heat dissipation properties, as evidenced by several studies. 84,85 Owing to their low density and excellent dielectric loss properties, CNTs have received significant attention in recent years for their ability to enhance electromagnetic wave (EMW) absorption and facilitate the development of lightweight and efficient EMW absorbing materials. 86,87 In a study, Zhu et al 88 used a simple solvothermal method to immobilize Fe 3 O 4 porous spheres on CNTs to obtain Fe 3 O 4 / CNT nanocomposites with a three-dimensional mesh structure.…”

Lightweight, Compressible, and Multifunctional Organic–Inorganic Nanofibrous Aerogels for Enhanced Microwave Absorption

“…11,12 The rich porosity endows the aerogels storing a high volume of air, which could not only reduce the density of the absorber to some extent but also optimize impedance matching to allow more microwaves enter to the absorber. 13,14 The 3D interconnected structure can form an interconnected conductive network for enhancing conductive loss and create multiple reflecting and scattering to prolong the pathway of microwaves for intensifying attenuation of the microwave energy. 15,16 Furthermore, the 3D scaffold can integrate other nanoscale microwave absorbers, which further improves the impedance matching and enhances the microwave absorbing capability.…”

“…Carbon-based aerogels are regarded as a remarkable candidate for an ideal EMWA absorber, due to their rich porosity, 3D interconnected structure, excellent electrical conductivity, and good chemical stability. , The rich porosity endows the aerogels storing a high volume of air, which could not only reduce the density of the absorber to some extent but also optimize impedance matching to allow more microwaves enter to the absorber. , The 3D interconnected structure can form an interconnected conductive network for enhancing conductive loss and create multiple reflecting and scattering to prolong the pathway of microwaves for intensifying attenuation of the microwave energy. , Furthermore, the 3D scaffold can integrate other nanoscale microwave absorbers, which further improves the impedance matching and enhances the microwave absorbing capability. , Su et al made use of these advantages of carbon materials to prepare pure carbon aerogels and adjusted the directional structure of the aerogels by changing the carbonization temperature so that materials can achieve excellent EMWA performance . Moreover, the inherent hydrophobicity and thermal stability of carbon-based aerogels afford the absorbers potential applicated in more complex environments. , However, conventional carbon-based aerogels are fragile and easily collapse when subjected to external stress, which is the primary challenge that has to be solved before they can be widely used, especially for high-performance microwave absorbers. , …”