Ti ₃ C ₂ T x MXene/Silver Composite Foams For Lightweight, High‐Performance Electromagnetic Interference Shielding and Joule Heating

Thin, lightweight materials that combine high electromagnetic interference (EMI) shielding with multifunctional performance are growing in demand for wearables, the internet of things, and soft robotics. Here, we report 1.0 mm‐thick composite films based on etched melamine foam (EMF) coated with MXene that deliver a specific shielding efficiency (SSE) of 749.6 /g and an average shielding efficiency (SE) of 44.4 dB across 8–18 GHz. By incorporating a silver (Ag)‐based ink into the foam before MXene coating, the resulting MXene/Ag/EMF films achieve an average SE of 81.4 dB with an SSE of 212.5 /g. Beyond EMI performance, these composites maintain stable function up to 250 and endure over 1,000 bending cycles without loss of shielding effectiveness. MXene/Ag/EMF films also exhibit rapid Joule heating– reaching 160 under 0.8 V bias and cooling back to 20 in 90 s, highlighting its high thermal conductivity. Such a combination of lightweight structure, excellent shielding, thermal stability, and mechanical resilience makes these films attractive for applications in aerospace, medical devices, and next‐generation communication systems.