Electrostatic self-assembled NiFe2O4/Ti3C2Tx MXene nanocomposites for efficient electromagnetic wave absorption at ultralow loading level

Two-dimensional Ti 3 C 2 T x MXene nanosheets with excellent electrical conductivity and layered structure have shown great promising in electromagnetic wave (EMW) absorption. Here, MXene nanosheets with homogeneously anchored NiFe 2 O 4 nanoparticles (NiFe 2 O 4 /MXene) were prepared using facial electrostatic self-assembling and freeze-drying technique. Interestingly, the minimum reflection loss ( RL min ) of paraffin wax-based composites with only 3% NiFe 2 O 4 /MXene reached as low as − 41.83 dB, showing much stronger EMW absorption property than that of MXene nanosheets ( RL min  =  − 5.03 dB) at the same loading level. This can be mainly ascribed to the existence of NiFe 2 O 4 nanoparticle that can effectively prevent the self-stacking of MXene nanosheets, causing improved conduction loss. Besides, large amounts of heterogeneous interfaces between NiFe 2 O 4 nanoparticle and MXene can also produce additional interface polarization loss. More importantly, magnetic loss arising from the magnetic NiFe 2 O 4 nanoparticle is beneficial for good impedance matching, enabling more EMW to enter into the interior of composites to be dissipated. Furthermore, effective absorption bandwidth in the frequency range of 3.44–18 GHz can be achieved by adjusting the matching thickness of composites with 5% NiFe 2 O 4 /MXene. This study paves a way for preparing high-performance MXene-based EMW absorber at ultralow loading level. Graphical abstract Electrostatic self-assembled NiFe2O4/MXene nanocomposites exhibit excellent electromagnetic wave absorption performance based on the synergistic effect of bifillers