Optimally designed tri-layered wave-absorbing materials with unique morphological absorbers toward ultra-wideband absorption

The electromagnetic wave-absorbing materials provide an efficient solution to notable electromagnetic pollution issues. However, as for the design of ultra-wideband, layered absorbing materials remain a critical challenge in the field of wave absorption. This paper first designs a series of broadband tri-layered absorbing structures using the prepared hybridized absorbers of EG-TEA@Fe 3 O 4 @GO with wrinkled morphology and MoO 3 @MWCNT with necklace-like morphology, as well as common dielectric and magnetic absorbers via particle swarm optimization algorithm, determining the appropriate range of electromagnetic parameters for the transmission layer (0 <  ε ′ < 5, 0 <  ε ″ < 1; 0 <  μ ′ < 1, 0 <  μ ″ < 0.5), absorption layer (5 <  ε ′ < 7, 1 <  ε ″ < 2; 1 <  μ ′ < 1.2, 0.5 <  μ ″ < 0.7) and reflection layer ( ε ′ > 7, ε ″ > 2; μ ′ > 1.2, μ ″ > 0.7) in wideband absorbing materials. Based on these findings, tri-layered absorbing structure with a wider effective absorption bandwidth of 15.63 GHz, stronger stealth capability with maximum RCS reduction of 17.9 dB m 2 and relatively thinner thickness was constructed, which was consistent with the predicted result. The absorption mechanism of the designed tri-layered absorbing structure, dominated by dielectric loss below 4 GHz and magnetic loss above 4 GHz, as well as multiple reflections induced by the fabricated absorber’s unique morphologies, is analyzed through CST simulations and electromagnetic analysis. The tri-layered absorbing structures we developed demonstrate significant advantages over similar reported counterparts, indicating great potential for applications in the ultra-wideband absorption field, and providing an effective method for the fabrication of ultra-wideband absorbing materials via controlling each layer’s electromagnetic parameters to a suitable range and adjusting the unique morphology of the absorbers with high specific surface area. Graphical abstract