Highly Efficient EMI Shielding via 3D-printed CNT/SiC-SiO ₂ Architectures

The development of lightweight, mechanically robust, and high-performance electromagnetic interference (EMI) shielding materials is critical for next-generation electronic and communication systems.In this study, we report the design and fabrication of a 3D-printed CNT/PDMS composite with tunable composition and hierarchical architecture.The resulting composite exhibits exceptional mechanical resilience, supporting loads up to 250 times its own weight and recovering fully after experiencing 40% strain.During pyrolysis in an inert atmosphere, the PDMS matrix decomposes and transforms into a SiC-SiO2 ceramic phase that encapsulates the CNT network, thereby forming a hierarchically porous, multi-phase architecture.Notably, the CNT/SiC-SiO2 composite demonstrates outstanding EMI shielding effectiveness (SE) of 62 dB in the X-band (8-12 GHz), primarily attributed to absorption (SEA = 59.91 dB).This elevated absorption capability arises from synergistic effects including improved impedance matching, conduction loss, interfacial/dipole polarization, and multiple internal reflections within the hierarchically porous, multi-interface architecture.The "absorption-reflection-reabsorption" mechanism enables near-complete attenuation of incident electromagnetic waves.This work presents a scalable, 3D-printing-enabled strategy for fabricating multifunctional carbon-ceramic composites with superior EMI shielding performance, which can meet the requirement of aerospace, wearable electronics, and military applications.