Microwave absorption properties of Ag naowires/carbon black composites

The composite that can absorb the high-performance electromagnetic (EM) wave is constructed into a sandwiched structure composed of carbon black (CB)/ethylene-vinyl acetate (EVA) and Ag naowires (AgNWs). The AgNWs sandwiched between two CB/EVA layers are used to improve the absorption properties of composite. The effects of EVA-to-CB weight ratio, concentration and diameter of AgNWs with a thickness of 0.4 mm on microwave absorption are investigated. The results indicate that for an EVA-to-CB weight ratio of 1:3, AgNW concentration of 1.0 mg/100 mL, and average diameter of 56 nm, the reflection loss (RL) of the composite is below -10 dB in a frequency range of 9.3 Ghz-18.0 GHz, with the minimum values of -40.0 dB and -25.6 dB at 13.5 GHz and 15.3 GHz, respectively. A finite element method (FEM) is used for calculating the RL of the composite. The calculated results are in agreement with the experimental data.