MXene-Based Microwave Absorbers

Different ways of synthesis were studied to tune physical properties of MXene. Depending on the synthesis method (etching, heat treatment), a wide range of electromagnetic properties can be achieved due to their abundant functional groups. MXene powders are thereafter incorporated into a polymer matrix and processed into thin films. The microwave characterization of the so-fabricated MXene-based composites showed that both high permittivity materials with medium loss tangent and high permittivity resistive materials can be obtained. Simulation suggests that these unusual properties can be used to decrease the absorption frequency of a Salisbury screen without increasing its thickness. In the light of these findings, a MXene-based composite was used to manufacture a Salisbury absorber that showed an absorption of 27.4 dB at 6.57 GHz. The resonance frequency is reduced by over 41% compared with a standard Salisbury screen, thanks to the high permittivity of MXene composites. These results pave the way for the design of thin, efficient microwave absorbers.