Graphene Composites as Efficient Electromagnetic Absorbers in the Extremely High Frequency Band

Zahra Barani; Fariborz Kargar; Konrad Godziszewski; Adil Rehman; Yevhen Yashchyshyn; Sergey Rumyantsev; Grzegorz Cywiński; Wojciech Knap; Alexander A. Balandin

doi:10.1021/acsami.0c06729

arXiv · 2004.06026

Graphene Composites as Efficient Electromagnetic Absorbers in the Extremely High Frequency Band

Zahra Barani·Fariborz Kargar·Konrad Godziszewski·Adil Rehman·Yevhen Yashchyshyn·Sergey Rumyantsev·Grzegorz Cywiński·Wojciech Knap·Alexander A. Balandin

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Abstract

We report on the synthesis of the epoxy-based composites with graphene fillers and testing their electromagnetic shielding efficiency by the quasi-optic free-space method in the extremely high frequency (EHF) band (220 - 325 GHz). The curing adhesive composites were produced by a scalable technique with a mixture of single-layer and few-layer graphene layers of a few-micron lateral dimensions. It was found that the electromagnetic transmission, T, is low even at small concentrations of graphene fillers: T<1% at frequency of 300 GHz for a composite with only 1 wt% of graphene. The main shielding mechanism in composites with the low graphene loading is absorption. The composites of 1 mm thickness and graphene loading of 8 wt% provide excellent electromagnetic shielding of 70 dB in the sub-terahertz EHF frequency with negligible energy reflection to the environment. The developed lightweight adhesive composites with graphene fillers can be used as electromagnetic absorbers in the high-frequency microwave radio relays, microwave remote sensors, millimeter wave scanners, and wireless local area networks.

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Zahra Barani, Fariborz Kargar, Konrad Godziszewski, Adil Rehman, Yevhen Yashchyshyn, Sergey Rumyantsev, Grzegorz Cywiński, Wojciech Knap, Alexander A. Balandin. 2020-04-13. Graphene Composites as Efficient Electromagnetic Absorbers in the Extremely High Frequency Band. https://doi.org/10.1021/acsami.0c06729

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