Synthesis and microwave absorption properties of MOF-derived NiO/NiFe2O4@Ti3C2TX nanosheets

In modern society with advanced electronic communication technology, electromagnetic wave absorbers are crucial in military and daily life. As electronic devices update rapidly, there's a need for absorbers with stronger absorption, wider bandwidth, and lighter weight. Emerging two-dimensional MXenes, with excellent dielectric properties and a unique nanosheet structure, have great microwave absorption potential. However, their practical use is limited by impedance mismatch due to high conductivity, causing poor reflection loss. To solve this, we report a novel NiO/NiFe₂O₄@Ti₃C₂Tₓ composite made by simple coprecipitation and 2-hour annealing at 400°C. Core-shell NiO/NiFe₂O₄ nanocubes were evenly anchored on MXene nanosheets, introducing magnetic loss mechanisms and modulating dielectric response via defect engineering. The NiO/NiFe 2 O 4 @Ti 3 C 2 T X composite material reached a minimum reflection loss of −46.05 dB at 16.83 GHz, and the effective absorption bandwidth (EAB) was 6.39 GHz at a thickness of 2.2 mm. This work offers a new strategy for designing high-performance microwave absorbers for aerospace stealth coatings.