Bioinspired Polyimide/Carbon Nanotube Aerogels With Core‐Radiating and Omasum‐Like Morphology toward Excellent Electromagnetic Shielding and Superior Elasticity

Abstract Lightweight polymer‐based electromagnetic interference (EMI) shielding materials exhibiting good mechanical adaptability and thermal stability are pivotal for next‐generation electronics. However, conventional approaches utilized to enhance the EMI shielding efficiency ( SE ) through porous architectures often compromise the structural integrity of the material or its EMI shielding performance under dynamic deformation. Herein, a morphogenetic approach is proposed to precisely coordinate the precursor thermodynamics by tuning the carbon nanotube (CNT) content and precursor concentration in the framework of the freeze‐drying method. With this method, polyimide/CNT aerogels with unprecedented triaxial hierarchical architectures (macroscopic core‐radiating patterns, microscopic omasum‐like folds, and nanoscopic CNT bridges) are obtained. The synergy between these multiscale structures extends the dissipation pathways of electromagnetic waves by inducing multiple reflections, yielding an EMI SE of 71 dB and an ultrahigh specific efficiency (6470 dB cm 2 g −1 ). Remarkably, the C67‐5.0 aerogels also exhibit enhanced EMI shielding performance with temperature (5.0% improvement at 350 °C), a negative Poisson's ratio (around −0.28), and structural stability (≈90% height retention after 500 compression cycles). This unique combination of a high EMI SE, outstanding mechanical properties, and excellent structural compressibility opens new avenues for designing adaptive EMI shielding systems for application to aerospace and electronics industries.