Ultralight Hierarchical\nFe₃O₄/MoS₂/rGO/Ti₃C₂T_<i>x</i> MXene Composite Aerogels for\nHigh-Efficiency Electromagnetic\nWave Absorption

Abstract

Aerogel-based composites, renowned for their three-dimensional\n(3D) network architecture, are gaining increasing attention as lightweight\nelectromagnetic (EM) wave absorbers. However, attaining high reflection\nloss, broad effective absorption bandwidth (EAB), and ultrathin thickness\nconcurrently presents a formidable challenge, owing to the stringent\ndemands for precise structural regulation and incorporation of magnetic/dielectric\nmulticomponents with synergistic loss mechanisms within the 3D networks.\nIn this study, we successfully synthesized a 3D hierarchical porous\nFe₃O₄/MoS₂/rGO/Ti₃C₂T_<i>x</i> MXene (FMGM) composite aerogel\nvia directional freezing and subsequent heat treatment processes.\nOwing to their ingenious structure and multicomponent design, the\nFMGM aerogels, featured with abundant heterogeneous interface structure\nand magnetic/dielectric synergism, show exceptional impedance matching\ncharacteristics and diverse EM wave absorption mechanisms. After optimization,\nthe prepared ultralight (6.4 mg cm^–3) FMGM-2 aerogel\nexhibits outstanding EM wave absorption performance, achieving a minimal\nreflection loss of −66.92 dB at a thickness of 3.61 mm and\nan EAB of 6.08 GHz corresponding to the thickness of 2.3 mm, outperforming\nmost of the previously reported aerogel-based absorbing materials.\nThis research presents an effective strategy for fabricating lightweight,\nultrathin, highly efficient, and broad band EM wave absorption materials.