Multi-components matching manipulation of MXene/PPy@β2-SiW11Co/Fe3O4 nanocomposites for enhancing electromagnetic wave absorption performance

Abstract

Two-dimensional layered metal carbides (MXene) have a broad application prospect in electromagnetic absorption, but suffer from poor impedance matching, which limits the absorbing performance. Herein, an efficient nanocomposite absorber was successfully prepared via loading Co-substituted β2-keggin-type polyoxometalate doped with polypyrrole and Fe3O4 on the surface of MXene. Polyoxometalate and HCl as a proton acid doped polypyrrole, with anions attached to the main chain, could adjust the electromagnetic parameters, making the nanocomposites material easily achieve the best conductivity and impedance matching; Fe3O4 introduced magnetic loss, and the freedom of movement of Fe2+ and Fe3+ caused multiple polarization; dipole polarization was induced by defects, dipoles and dangling bonds in nanocomposites; the charge accumulated at the three phase interface and led to interfacial polarization. We had conducted research on the absorbing properties of nanocomposites with different as-prepared unitary to ternary products, loading rates and component proportion. When the filling level was 45 wt%, an optimal reflection loss value of MXene/PPy@β2-SiW11Co/Fe3O4 nanocomposites at only 1.7 mm reached up to −62.6 dB, and the effective absorption bandwidth of 9 GHz could be obtained at the low thickness range of 1.5–2.9 mm. These results demonstrated that the prepared nanocomposites wereexpected to be a promising electromagnetic wave absorber with thin thickness and high absorption intensity.