Multifunctional carbon aerogels loaded with pea-pod-like carbon nanotubes for outstanding electromagnetic wave absorption performance

[Display omitted] •Pea-pod-like N-doped carbon nanotubes grow in situ on carbonised bacterial cellulose surface, forming an aerogel resembling pea plant microstructure.•The CoNi@CNTs-800 aerogel achieves an RLmin of −91.58 dB and an EAB of 7.68 GHz, demonstrating the largest absorption strength in all known aerogel.•The CoNi@CNTs-800 aerogel integrates thermal insulation, compressible elasticity and outstanding microwave absorption, showing multifunctionality. Although ordered porous carbon materials (PCMs) have shown promising potential in the field of electromagnetic wave absorption (EWA), creating multifunctional PCMs with outstanding microwave absorption performance remains a significant challenge. Herein, ordered porous carbon aerogels loaded with pea-pod-like nitrogen-doped carbon nanotubes (CNTs) were fabricated via orientation freeze-drying followed by high-temperature pyrolysis. The optimized aerogel exhibits extraordinary EWA performance with a broad effective absorption bandwidth of 7.68 GHz and exceptionally strong absorption of −91.58 dB at a low filling ratio of only 3 wt%, which is the largest absorption strength among all known aerogels to date. The exceptional EWA performance is attributed to the synergistic effect of abundant loss mechanisms resulting from a unique pod-like structure in ordered porous carbon aerogel, where nitrogen-doped CNTs encapsulate magnetic alloy nanoparticles. Optimized aerogel exhibits superior compressive elasticity, thermal insulation, and light weight, laying the groundwork for designing practical next-generation EWA materials.