Optimization design of patterned rGO metasurface structures guided by electromagnetic simulation towards broadband electromagnetic wave absorption

The traditional approach to reducing the reflection loss (RL) of microwave absorption (MA) materials involves compositional design and microstructural design. Nevertheless, this method commonly struggles to attain the desired effective absorption bandwidth (EAB), consequently constraining its practicality. In the field of radar frequency electromagnetic waves, The comprehensive strategy of combining macroscopic structural design with material composition has been proven effective in achieving broadband absorption capacity. Herein, a patterned reduced graphene oxide (rGO) based metasurface structure through electromagnetic simulation guidance has been invented, which has the characteristics of lightweight, ultra wideband and efficient MA capability. Metasurface structure was designed by introducing homocentric square shape and cross shape into gradient structure, which were named as Top homocentric square-shaped structure (T-HS), Bottom cross-shaped type structure (B-CS) and Bottom homocentric square-shaped structure (B-HS). The impedance matching and attenuation capabilities were enhanced by mutual, multiple reflections and scattering among periodic units. Therefore, the materials attained more significant MA performance at the same thickness. The simulation results revealed that the structural designs adjust the resonance frequency, leading to the formation of dual absorption peaks at 9.29 GHz and 16.02 GHz, which significantly broadened the EAB to 10.49 GHz with the RL of −75.7 dB. Furthermore, The arch experimental test confirmed the effectiveness of patterned metasurface structure design, extending the EAB from 3.29 GHz to 12.85 GHz and the RL_max from −25.20 dB to −30.75 dB. The patterned rGO metamaterials hold great promise for application in broadband electromagnetic protection.