Broadband and Tunable High‐Performance Microwave Absorption of an Ultralight and Highly Compressible Graphene Foam

Abstract

The broadband and tunable high-performance microwave absorption properties of an ultralight and highly compressible graphene foam (GF) are investigated. Simply via physical compression, the microwave absorption performance can be tuned. The qualified bandwidth coverage of 93.8% (60.5 GHz/64.5 GHz) is achieved for the GF under 90% compressive strain (1.0 mm thickness). This mainly because of the 3D conductive network.

Silane bonded graphene aerogels with tunable functionality and reversible compressibility

“…With the increase of SCA/GO weight ratio from 1 to 10, denser porous structures with smaller, irregular shaped pores (e.g. from ~50 µm for S2-1 to ~20 µm for S2- 11 10 in average size) are obtained (Fig. 2b-e and Fig.…”

“…Two-dimensional (2D) graphene sheets exhibiting extraordinary high specific surface area [4,5], high intrinsic stiffness and strength [6], high electrical/thermal property [7,8] have been exploited in three-dimensional (3D) graphene foams [9][10][11] or aerogels [12][13][14]. These 3D graphene structures with low-density and versatility show great promise for a broad range of applications in the fields of catalysis, sensor, electronics, energy storage/conversion, oil/water separation [14][15][16][17][18][19][20][21][22].…”

Multiscale Assembly of Grape-Like Ferroferric Oxide and Carbon Nanotubes: A Smart Absorber Prototype Varying Temperature to Tune Intensities

“…[6][7][8] Although good MA performance appears in some cases, the drawbacks, including high density, large thickness and high loading content, have severely limited their practical applications. Recent years, carbon materials, such as ordered mesoporous carbon, 9 carbon nanotubes, 10-18 carbon nanocoils, 4 reduced graphene oxides and graphene, [19][20][21][22][23][24][25][26][27][28] etc., exhibit potential application in MA. Multi-walled carbon nanotubes (MWCNTs) and their heterostructures, as lightweight absorbers, have been extensively 3 researched due to the high specific surface areas and carrier mobility.…”

Dependency of tunable microwave absorption performance on morphology-controlled hierarchical shells for core-shell Fe3O4@MnO2 composite microspheres

“…Based on the free electron theory, ߝ ᇱᇱ ≈ 1 ߨߝ ߩ݂ ⁄ , where ߩ is the resistivity, the high ߝ ᇱᇱ value means the low resistivity, which illuminates the good electronic transmission performance and excellent conductivity [14,43]. It can be inferred that the conductive loss exists and the high conductivity may stem from the generation of microcurrent in the special microstructure with the altering electromagnetic field [36,[44][45]. In addition, the interfaces between the In the analysis of microwave absorption mechanism, it is necessary to take into account the impedance matching and attenuation constant.…”