Dual template-derived 3D porous Co6 Mo6 C2 /Mo2 C@NC framework for electromagnetic wave response and multifunctional applications

The swift advancement of electronics technology has led to a burgeoning interest in multifunctionalizing electromagnetic wave (EMW) absorption materials as a prospective avenue for future development. However, the effective integration of diverse functions within a single material continues to present challenges. This work successfully fabricated a three-dimensional (3D) porous Co6 Mo6 C2 /Mo2 C@NC framework with carbon microspheres through uncomplicated freeze-drying and high-temperature pyrolysis techniques. The resultant magnetic bimetallic carbide (Co6 Mo6 C2 and Mo2 C) nanoparticles are uniformly and densely embedded within the carbon layer, facilitated jointly by a rigid template (molybdenum salt) and a flexible template (glucose), thus realizing an exceptional dual loss mechanism involving dielectric and magnetic components. The establishment of the 3D porous conductive network enhances EMW absorption through multiple reflections and scattering mechanisms. Impressively, the Co6 Mo6 C2 /Mo2 C@NC framework attains remarkable EMW absorption characteristics with ultralightweight (0.1567 g cm-3 ), ultrathin matching thickness (1.7 mm), and robust absorption (reflection loss RL value of -65.89 dB). Furthermore, it achieves a noteworthy effective absorption bandwidth (EAB, RL <= -10 dB) spanning 6.4 GHz, ensuring complete absorption of 100 % within the X band (8-12 GHz) at a matching thickness of 2 mm. In addition, the Co6 Mo6 C2 /Mo2 C@NC framework exhibits pronounced hydrophobicity and magnetic responsiveness, bestowing upon it appealing attributes including self-cleaning, flame retardancy, and thermal insulation, on par with those observed in commercial products. The radar cross-sectional area (RSC) reduction value of the Co6 Mo6 C2 /Mo2 C@NC framework can reach 35.2 dB m2 by RSC simulation, which can effectively lower the likelihood of detection by radar detectors for the target. This study presents a viable strategy for the advancement of novel lightweight and multifunctional materials that demonstrate exceptional performance in absorbing electromagnetic waves. (c) 2024 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.