Window Grilles‐Inspired Detachable and Heatable AgNWs/PU Composite Films for Indoor Electromagnetic Interference Shielding

Abstract Long‐time indoor exposure to electromagnetic waves generated by electronic devices has posed a threat to the health of young life. The threat may intensify in low‐temperature environments due to low immunity. Prolific endeavors have focused on developing electromagnetic interference (EMI) shielding materials but failed to meet the visible, portable, and temperature‐controllable indoor‐use requirements. Herein, a detachable and heatable AgNWs/PU composite film is fabricated by facile spray coating and quick melting. The half‐inserted 3D network structure of AgNWs on PU ensures stable and high conductivity, thus endowing sufficient EMI shielding performance at 27 dB for indoor use. The high transparency (≥73.2%) and strong electrostatic force enable the detachable and portable use of the composite film. The resulting Joule heat at the voltage of 5 V endows a heatable property, which raises to 44.8 °C within 60 s. The AgNWs/PU composite film can self‐adhere in an indoor protective chamber, enabling visual monitoring and blocking electromagnetic radiation while keeping a comfortable inside temperature. The facile fabrication makes the self‐adhesive and multifunctional film possible in large‐scale production for practical application.