In-situ anchoring of Fe3O4/ZIF-67 dodecahedrons in highly compressible wood aerogel with excellent microwave absorption properties

Abstract

Lightweight aerogels with superior cavities have attracted great interest in the field of electromagnetic wave absorbing materials. In this work, a hierarchical porous wood aerogel modified with Fe3O4/ZIF-67 (Fe3O4/ZIF-67@WA) with high compressibility and low-density was fabricated by in-situ anchoring of magnetic Fe3O4/ZIF-67 rhombohedral dodecahedron in naturally delignified wood aerogel. Combining the advantages of both aerogels and magnetic Fe3O4/ZIF-67 particles, Fe3O4/ZIF-67@WA reveals excellent compression-resilience and efficient microwave absorption performance. It possesses a maximum reflection loss (RL) of about −23.4 dB at a low thickness of 1.5 mm and a specific electromagnetic shielding effectiveness of up to ~156.3 dB cm3 g−1. Moreover, the composites exhibit a broad absorption bandwidth under an ultrahigh frequency of 13.5–18.0 GHz. In view of those excellent absorbing effects, the prepared green magnetic Fe3O4/ZIF-67@WA is likely to be used as a lightweight shielding material against electromagnetic radiation, especially for smart building and miniaturized device applications.