In Situ Polyurea Integration for Self‐Healing, Durable Transparent Electromagnetic‐Interference Shielding Film

Scalable fabrication of transparent electromagnetic-interference (EMI) shielding films that combine durability with long-range conductivity is in high demand for flexible electronics and the Internet of Things (IoT). Yet, scaling such shields remains challenging because of their vulnerability to chemical corrosion and mechanical deformation. Here, we report an in situ integration strategy by molecular engineering that retards polyurea curing kinetics to suppress crystallization, yielding a highly transparent, ultraflexible secondary-amine polyurea (PuSA) with an ultra-flat surface and self-healing capability. The extended wetting-to-gelation window allows void-free sandwiching of hierarchical conductive networks composed of 2D MXene nanosheets coated with 1D silver nanowires (AgNWs). The resulting PuSA@AgNWs/MXene@PuSA (AMP) film delivers commercial-grade optoelectronics, rapid multi-triggered self-healing, and ultrabroadband EMI shielding from the gigahertz (GHz) to the terahertz (THz) range. Notably, it retains over 95% of its initial EMI shielding effectiveness (SE) under rigorous chemical, thermal, UV aging, and mechanical challenges. This work thus establishes a general, scalable route to translate fragile nanoconductors into high-performance, rugged transparent shields with broadband protection and long-term reliability in next-generation displays and wearable electronics.