Multidimensional nanomaterials synergistic polyimide nanofiber/MXene/NiFe2O4 hybrid aerogel for high-performance microwave absorption

Microwave absorption materials are urgently demanded to control the increasing electromagnetic radiation pollution, but it remains a great challenge to achieve high-performance absorption through ingenious structure design and reasonable multicomponent strategy. Herein, a three-dimensional (3D) hybrid aerogel constructed from multidimensional nanomaterials was fabricated via freeze-drying method followed by heating treatment process. Therein, 2D Ti3C2Tx MXene nanosheets and 0D NiFe2O4 nanoparticles act as the electrical-magnetic skeleton of aerogel, while 1D polyimide nanofibers and polydimethylsiloxane as internal supporting parts and external crosslinker, respectively. The macroscopic interconnected porous structure coupled with the microscopic multiphase heterointerfaces are beneficial to forming the perfect impedance matching and superior dielectric/magnetic synergistic loss effects. Thus, the microwave absorption performance of this hybrid aerogel achieves thin thickness (1.5 mm), light weight (∼9.6 mg/cm3), wide effective absorption bandwidth (−6.24 GHz), and strong absorption (minimum reflection loss of −64.87 dB, 99.99996% microwave absorption) features. Besides, this aerogel also exhibits exceptional structural robustness and mechanical properties, as well as good hydrophobicity and thermal insulation characteristics, which ensure its stable and durable microwave absorption application in complex environments. This study effectively integrates multidimensional nanomaterials into a host–guest aerogel system, providing a valuable strategy for constructing high-performance microwave absorption materials.