Lightweight, Flexible, and Thermal Insulating Carbon/SiO₂@CNTs Composite Aerogel for High‐Efficiency Microwave Absorption

Abstract

A complex electromagnetic environment is a formidable challenge in national defense areas. Microwave‐absorbing materials are considered as a strategy to tackle this challenge. In this work, lightweight, flexible, and thermal insulating Carbon/SiO2@CNTs (CSC) aerogel is successfully prepared coupled with outstanding microwave absorbing performance, through freeze‐drying and high‐temperature annealing techniques. The CSC aerogel shows a strong reflection loss (−55.16 dB) as well as wide effective absorbing bandwidth (8.5 GHz) in 2–18 GHz. It also retains good microwave absorption properties under tension and compression. Radar cross‐sectional (RCS) simulation result demonstrates the CSC processing a strong reduction ability of RCS compared with a metal plate. Further exploration shows amazing flexibility and good thermal insulation properties of CSC. The successful preparation of this composite aerogel provides a broad prospect for the design of microwave‐absorbing materials.

Enhancing Low-Frequency Microwave Absorption Through Structural Polarization Modulation of MXenes

“…S6 and Fig. S6 ), when the thickness reaches one-fourth of the wavelength of the incident wave, an interference cancellation occurs between the incident wave and the reflected wave, and in this case the thickness is the optimal thickness corresponding to the matching frequency [ 43 , 75 ]. Figure S5 shows that the measured matching thickness is basically consistent with the simulated thickness of the half-wavelength loss.…”

In Situ Synthesis of an Epoxy Resin Microwave Absorption Coating with Anti-Ultraviolet Aging Effects

“…RL ≤ −10 dB was defined as effective absorption. According to transmission line theory and the electromagnetic parameters measured in the 2-18 GHz range, the corresponding RL was calculated according to the following equations [39]: In general, reflection loss (RL) is used to evaluate the MA performance of a material. RL ≤ −10 dB was defined as effective absorption.…”

“…RL ≤ −10 dB was defined as effective absorption. According to transmission line theory and the electromagnetic parameters measured in the 2-18 GHz range, the corresponding RL was calculated according to the following equations [39]:…”

Ultralight Hierarchical Fe3O4/MoS2/rGO/Ti3C2Tx MXene Composite Aerogels for High-Efficiency Electromagnetic Wave Absorption

“…Electromagnetic (EM) waves serve as crucial carriers of energy in various communication technologies; however, the widespread proliferation of electronic devices and wireless communication technologies has inevitably led to EM wave pollution, which causes interference risks to precision instruments and potential threat to human health. , To tackle these problems, researchers have developed various EM wave absorption materials, including traditional magnetic materials, dielectric materials, − metal–organic frameworks (MOFs), − and carbon-based materials such as carbon nanotubes (CNTs) and carbon fiber (CF). − Recently, with the trend toward miniaturization and lightweight design in electronic and communication devices, the demand for EM wave absorbers that are ultralight, ultrathin, highly efficient, and capable of broad bandwidth absorption has intensified. This development trend renders conventional magnetic or dielectric powder and single-component carbon-based materials inadequate for practical application.…”