Sustainable Synthesis of Bio‐Based Magnetic and Conductive Wood for Electromagnetic Interference Shielding Applications

The rapid proliferation of smart electronics and 5G/6G wireless infrastructure has heightened environmental and operational concerns associated with electromagnetic wave (EMW) pollution. Extended EMW exposure is implicated in adverse health outcomes and induces electromagnetic interference (EMI) that undermines the reliability of advanced electronic and power distribution systems. To address these challenges, a solvent‐free, two‐step synthesis introduces a sustainable, wood‐derived EMI shielding material, “Magwood (MW).” This approach integrates vacuum‐assisted FeCl 2 impregnation (0–3 m ) with direct N 2 pyrolysis (400–1000 °C), eliminating the need for organic solvents, delignification, or any harsh chemical treatment to synthesize in situ metal crystals, thereby advancing green‐chemistry principles. This scalable method generates a hierarchically porous, magnetic, and electrically conductive structure that can be implemented for any wood species. Optimizing the precursor concentration (1 m ) and pyrolysis temperature (800 °C) yields a saturation magnetization of 25.2 emu g −1 , an electrical conductivity of 24.3 S cm −1 , and a total shielding effectiveness (SE T ) of 45.9 dB (>99.99% attenuation of X‐band). MW additionally exhibits intrinsic hydrophobicity (static contact angle ≈99°) and self‐extinguishing behavior, endorsing its use in lightweight, sustainable EMI gaskets, casings, and architectural interlayers.