Design of Ti3C2Tx/TiO2/PANI multi-layer composites for excellent electromagnetic wave absorption performance

[Display omitted] •Synthesized accordion-like Ti3C2Tx MXene with large layer spacing.•Synthesized Ti3C2Tx/TiO2/PANI composites with sandwich structure.•The optimal absorption was up to −65.61 dB at 2.18 mm and EAB to 5.92 GHz at 2.10 mm. Ti3C2Tx MXene is an excellent electromagnetic wave (EMW) absorber with excellent electrical conductivity and abundant surface functional groups. In this research, Ti3C2Tx/TiO2/PANI multi-layer composites were successfully synthesized by HCl and LiF etching, one-step hydrothermal method and in-situ polymerization. Ti3C2Tx can provide more electron transfer paths due to its unique multilayer structure and high specific surface area. The growth of TiO2 particles on the surface of Ti3C2Tx through hydrothermal reaction enhances the interface polarization, and then polyaniline (PANI) is doped on the surface of Ti3C2Tx where TiO2 particles are grown by in-situ polymerization. Due to the excellent dielectric properties and synergistic effects of the material itself, Ti3C2Tx/TiO2/PANI composites have excellent EMW absorption property. In this study, the Ti3C2Tx/TiO2/PANI composites showed the strong reflection loss (RL) of at 13.92 GHz, which was −65.61 dB, and the thickness was only 2.18 mm. Moreover, the composites also exhibit a wide absorption band, with an effective absorption bandwidth (RL