MOF-Derived\nCo/C and MXene <i>co</i>-Decorated\nCellulose-Derived Hybrid Carbon Aerogel with a Multi-Interface Architecture\ntoward Absorption-Dominated Ultra-Efficient Electromagnetic Interference\nShielding

Abstract

Exploring\nelectromagnetic interference (EMI) shielding materials\nwith ultra-efficient EMI shielding effectiveness (SE) and an absorption-dominated\nmechanism is urgently required for fundamentally tackling EMI radiation\npollution. Herein, zeolitic imidazolate framework-67 (ZIF-67)/MXene/cellulose\naerogels were first prepared via a simple solution mixing-regeneration\nand freeze-drying process. Subsequently, they are converted into electric/magnetic\nhybrid carbon aerogels (Co/C/MXene/cellulose-derived carbon aerogels)\nthrough a facile pyrolysis strategy. ZIF-67-derived porous Co/C could\nprovide the additional magnetic loss capacity. The resultant electric/magnetic\nhybrid carbon aerogels exhibit a hierarchically porous structure,\ncomplementary electromagnetic waves (EMWs) loss mechanisms, and abundant\nheterointerfaces. The construction of a porous architecture and the\nsynergy of electric/magnetic loss could greatly alleviate the impedance\nmismatching at the air–specimen interface, which enables more\nEMWs to enter into the materials for consumption. Moreover, numerous\nheterointerfaces among Co/C, Ti₃C₂T_<i>x</i> MXene, and cellulose-derived carbon skeleton induce\nthe generation of multiple polarization losses containing interfacial\nand dipole polarization, which further dissipate the EMWs. The resultant\nelectric/magnetic hybrid carbon aerogel with a low density (85.6 mg/cm³) achieves an ultrahigh EMI SE of 86.7 dB and a superior absorption\ncoefficient of 0.72 simultaneously. This work not only offers a novel\napproach to design high-performance EMI shielding materials entailing\nlow reflection characteristic but also broadens the applicability\nof electric/magnetic hybrid carbon aerogels in aerospace, precision\nelectronic devices, and military stealth instruments.