Direct‐Ink‐Writing Printed Aerogels with Dynamically Reversible Thermal Management and Tunable Electromagnetic Interference Shielding

Abstract Achieving both structural precision and tunable performance in electromagnetic interference (EMI) shielding materials remains a critical challenge, particularly for adaptive applications. Herein, a strategy is proposed that integrates calcium chloride (CaCl₂)‐induced elastic activation of carboxymethyl cellulose (CMC) with direct ink writing (DIW) 3D printing to address the limitations in structural design and performance adjustability of EMI shielding materials. By leveraging CaCl₂‐crosslinked CMC (CCMC) as a flexible matrix, honeycomb‐structured (Ti₃C₂T x /Fe₃O₄/CCMC)–(Ag nanowire (AgNW)/CCMC) aerogels is fabricated with precise architecture and tunable shielding effectiveness under mechanical compression. With a 35% printing fill density, 40 wt% Ti₃C₂T x , and 60% compressive strain, the aerogel achieves an optimal shielding effectiveness of 80 dB. Additionally, the aerogel exhibits reversible infrared stealth and dynamically switchable thermal properties (from 0.08 to 0.67 W·m⁻¹·K⁻¹) in response to environmental humidity variations. This work demonstrates a versatile approach for structurally adaptive EMI shielding materials with self‐regulating thermal behavior, offering promising applications in harsh environment protection, intelligent thermal camouflage, and adaptive shielding for next‐generation aerospace and communication technologies.