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Research Article

Metasurface-assisted low-frequency performance enhancement of ultra-broadband honeycomb absorber based on carbon nanotubes

Cai-Liang Wang1,2, Shuang Bai1, Pei-Yan Zhao1, Tao Zhou4, Hui-Ya Wang5, Jun-Peng Wang2( ), Luo-Xin Wang3, Guang-Sheng Wang1( )
School of Chemistry, Beihang University, Beijing 100191, China
Aerospace Science and Industry Corporation of Wuhan Magnetoelectricity Co., Ltd., Wuhan 430070, China
College of Materials Science and Engineering, Key Laboratory for New Textile Materials and Applications of Hubei Province, Wuhan Textile University, Wuhan 430200, China
School of Chemistry and Chemical Engineering, Lingnan Normal University, Zhanjiang 524048, China
School of Materials Science and Engineering, Zhejiang Sci-Tech University, Hangzhou 310018, China
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Graphical Abstract

A method for improving low-frequency absorption performance and designing a broadband absorber of honeycomb absorber (HA) by placing a metasurface between two absorptive honeycombs was proposed. A prototype sample has been created and evaluated to validate the approach and concept, which demonstrates high efficiency and broadband absorption with average absorption rates exceeding 90% over the whole frequency range from 1.0 to18.0 GHz.

Abstract

Here, we present a unique method to enhance the low-frequency absorption performance of a honeycomb absorber by integrating a metasurface. The geometrical dimensions of the proposed metasurface have been numerically optimized. The introduction of the metasurface allows exploitation of its robust resonance and superior impedance matching in low-frequency bands, thereby improving microwave absorption properties. The incorporation of the metasurface does not impact the wave transmission performance of the honeycomb core absorber at high-frequency band, thus preserving its high-frequency performance. This broadens the absorption range, leading to an expanded bandwidth. Simulation results reveal that the composite absorber (CA) exhibits strong absorption performance with an incident angle stability up to 45° for both transverse electric (TE) and transverse magnetic (TM) modes. The absorption mechanism of the CA has been investigated by using an equivalent circuit model and electromagnetic field analysis. A prototype was designed, fabricated, and tested to validate the proposed method. Both simulation and measurement results demonstrate that the prototype can achieve an average absorption rate exceeding 90% across a 1.0−18.0 GHz range. This study introduces an innovative technique for creating microwave absorbers for low-frequency wideband applications.

Keywords

low frequencymetasurfaceradar absorptionimpedance matching

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Nano Research
Volume 17 Issue 9,
September 2024
Pages 8542-8551
DOI: 10.1007/s12274-024-6833-9
Cite this article:
Wang C-L, Bai S, Zhao P-Y, et al. Metasurface-assisted low-frequency performance enhancement of ultra-broadband honeycomb absorber based on carbon nanotubes. Nano Research, 2024, 17(9): 8542-8551. https://doi.org/10.1007/s12274-024-6833-9
Topics:
Carbon nanotubes
Part of a topical collection:
EM Wave Functional Materials

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Received: 23 May 2024
Revised: 14 June 2024
Accepted: 17 June 2024
Published: 03 August 2024
© Tsinghua University Press 2024
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