Three-Dimensional Magnetic Functionalized Graphene Composite Aerogels for Microwave Absorption: A Review

Abstract

Graphene-based microwave-absorbing materials (MAMs), especially graphene aerogels (GAs), have attracted tremendous attention because of their excellent characteristics. Three-dimensional (3D) GA materials exhibit a complex porous network structure, which is conducive for enhancing the loss capacity because of multiple reflections and scatterings. Compared to the typical two-dimensional graphene-based absorbing materials, GA materials with a special 3D network and an internal porous structure can solve the phenomenon of graphene sheet layer agglomeration and impedance mismatch, achieving better electromagnetic absorption characteristics. Combining the magnetic materials with GA can realize an ultrawide-band electromagnetic response and improve the microwave absorption (MA) performances of the 3D GA composites. Herein, we summarize the theories of MA and the recent progresses in magnetic GA materials. On this basis, we propose the perspectives and challenges of magnetic GA MAMs and discuss the multifunctional absorbing materials.

Review of Three-Dimensional Graphene and Related Composite Materials for Microwave Absorption

“…45,46 Therefore, it is necessary to review and organize the preparation methods of 3DG and the current research status of 3DG-based composite MAMs. Compared to previous review articles, 47,48 this article provides a more comprehensive summary of the preparation methods of 3DG, including template method, nontemplate method, and 3D printing method, and analyzes their advantages and disadvantages. This review serves as a valuable reference for other researchers in the field of 3DG preparation.…”

“…In addition, the type of material used for composite has a significant impact on the attenuation coefficient and impedance matching performance of 3DG-based composite materials, which in turn plays a decisive role in the final MA performance. , Therefore, it is necessary to review and organize the preparation methods of 3DG and the current research status of 3DG-based composite MAMs. Compared to previous review articles, , this article provides a more comprehensive summary of the preparation methods of 3DG, including template method, nontemplate method, and 3D printing method, and analyzes their advantages and disadvantages. This review serves as a valuable reference for other researchers in the field of 3DG preparation.…”

Effect of Surface Characteristics of Graphene Aerogels and Hydrophilicity of Ionic Liquids on the CO2/CH4 Separation Performance of Ionic Liquid/Reduced Graphene Aerogel Composites

“…Graphene-based materials are getting increasing attention thanks to their interesting features, such as high mechanical stability, thermal conductivity, tunability, and applicability to various fields . Graphene aerogels (GAs), as one of the subclasses of graphene-based materials, come forward since they offer ultralow density, high surface area, and high thermal–electrical conductivity. , Different than graphene’s 2D structure, where sp 2 -hybridized, covalently bonded carbons are packed in a hexagonal skeleton, a typical GA structure is in a 3D form because of the formation of a highly porous network following the specialized treatment of commonly used graphene oxide (GO) solution . Several methods have been reported to synthesize these 3D structured materials, such as sol–gel polymerization, freeze–drying of GO solution, and one-pot hydrothermal treatment of GO solution without any addition of other chemicals .…”

Influence of Exfoliated Boron Nitride for Fabrication of a Lightweight Wideband Microwave Absorbing Material

“…The absorption property depends on materials’ conductivity, impedance matching, and microstructures. − For microwave absorption, many composite materials are developed, including dielectric materials for dielectric loss, magnetic materials for hysteresis and eddy current loss, and conducting materials for electrical loss and multiple reflections. Individually, however, they exhibit limited bandwidth absorption. , Researchers use a combination of dielectric, magnetic, and conducting materials to achieve wideband microwave absorption.…”

“…Individually, however, they exhibit limited bandwidth absorption. 14,15 Researchers use a combination of dielectric, magnetic, and conducting materials to achieve wideband microwave absorption.…”