Ag/CNT nanocomposites and their single- and double-layer electromagnetic wave absorption properties

[Display omitted] •Single- and double-layer EM wave absorber of Ag/CNT nanocomposites was evaluated.•Double-layer, S2 showed minimum reflection loss of ∼−52.9dB.•The thickness can be decreased to about half by utilizing double-layer absorber.•Wide response bandwidth can be obtained in several frequency regions. The electromagnetic wave absorption properties of single- and double-layer silver nanoparticle/carbon nanotube (Ag/CNT) nanocomposites were evaluated. The reflection loss (R.L.) of the samples was calculated based on the measured complex permittivity and permeability. The double-layer composites constructed from CNT 30wt.% and Ag/CNT 30wt.% with total thickness of 3.3mm showed a minimum R.L. of ∼−52.9dB (over 99.999% absorption) at 6.3GHz. The bandwidth of reflection loss less than −10dB was observed at 3 regions, with wideness of 3.5, 0.8, and 1.5GHz. Thin absorber with large R.L. and wide response bandwidth at low and high frequency regions can be obtained with double-layer composites. The capability to modulate the absorption and bandwidth of these samples to suit various applications in different frequency bands indicates that these nanocomposites could be an excellent electromagnetic wave absorber.