Tunable electromagnetic and enhanced microwave absorption properties in CoFe2O4 decorated Ti3C2 MXene composites

Ti3C2 MXene has demonstrated to be a potential microwave absorber if some difficulties, e.g., poor impedance matching and lack of magnetic loss, can be well-solved. In this paper, laminated Ti3C2 MXene was synthesized using the HF etching method. CoFe2O4 nanoparticles-decorated Ti3C2 MXene (CoFe2O4-Ti3C2) composites were then fabricated via a novel in-situ solvothermal process. The incorporation of CoFe2O4 nanoparticles on the electromagnetic (EM) and microwave absorption properties of Ti3C2 MXene were systematically studied over 2-18 GHz. Interestingly, increased percolation threshold and controlled complex permittivity were well-observed in the CoFe2O4-Ti3C2 composites. Furthermore, additional magnetic loss due to the existence of magnetic CoFe2O4 was easily obtained. Benefiting from tunable electromagnetic properties, the minimum reflection loss (RL) value of the CoFe2O4-Ti3C2-filled absorbing coating achieved -30.9 dB with a matching thickness of only 1.5 mm. A wide effective absorption bandwidth (RL < -10 dB) of 8.5 GHz was correspondingly realized. These results demonstrated that the CoFe2O4-Ti3C2 composites are favorable as a broadband microwave absorbent.