Confined high-entropy reconstruction of conductive carbon skeletons for thin and flexible electromagnetic shielding films.

Thin, flexible conductive carbon films require continuous charge-transport networks for efficient electromagnetic interference (EMI) shielding, yet enhancing their limited intrinsic dissipation through loss-active heterogeneity often compromises network continuity. Here, a rare-earth-regulated confined high-entropy reconstruction strategy is developed to build attenuation-active interfaces on a carbon nanotube (CNT) skeleton. At a fixed total metal loading, partial substitution of Fe/Co/Ni with Pr/Nd/Sm redirects reconstruction during millisecond flash Joule heating from an alloy-dominated state toward local alloy/oxide partitioning, kinetically trapping discrete high-entropy alloy/high-entropy metal oxide nanodomains along the CNT skeleton. The resulting dissipation-active heterogeneous CNT (DAHC) framework preserves skeleton-level electrical continuity, while its multiphase interfaces and defect-rich domains enhance interfacial charge redistribution and internal attenuation. In a compact bilayer architecture, the 0.96-mm-thick DAHC-3 bilayer film achieves an average total shielding effectiveness (SET) of 59 dB over 8-16 GHz and a band-averaged absorption power coefficient (A) of 0.82. Its average SET is 119% higher than that of the unmodified CNT film. The bilayer film also retains functional shielding under mechanical and environmental perturbations. DAHC-3 fragments can further be formulated into a composite ink for direct ink writing (DIW), yielding approximately 25 dB shielding in printed conformal components. This work establishes a transport-preserving route to integrate nanoscale loss heterogeneity with continuous conductive carbon skeletons for compact and conformal EMI shielding.