Multiphysical‐Coupled Microfiber Film for Closed‐Loop Electromagnetic Radiation “Perception‐Actuation‐Shielding”

ABSTRACT Electromagnetic (EM) shielding materials have attracted growing attention due to the exponential growth of EM sources and increasing persistence of EM exposure for both humans and precise instruments. However, current EM shielding materials mostly provide static shielding by passively blocking EM radiation. Achieving on‐demand EM shielding with automatic closed‐loop “perception‐actuation‐shielding” in a single material remains a formidable challenge. This work presents an intelligent fiber film (IFF) that couples electrical‐mechanical‐electromagnetic effects in a single film, achieving the EM sensing, actuation, and EM shielding capability, providing an ideal carrier to tackle this challenge. By constructing a layered hierarchical structure, EM induction‐based electric sensing and environmental factors‐triggered actuation functions are incorporated into the EM shielding material, without additional components introduced. This IFF can dynamically adapt to different geometries and scenarios by autonomous actuation to shield EM radiation when it detects the EM intensity exceeding the preset threshold. IFF‐based soft robots are demonstrated, which can move/deform to achieve on‐spot EM shielding. Through the coupling of electrical‐mechanical‐electromagnetic effects in the fiber film, this work achieves closed‐loop EM radiation “perception‐actuation‐shielding”, which provides a common strategy for the development of intelligent EM shielding materials with dynamic adaptivity for applications in microelectronics, intelligent buildings, and military/aerospace equipment.