Design of Ti₃C₂T_x/TiO₂/PANI multi-layer composites for excellent electromagnetic wave absorption performance

Ti₃C₂T_x MXene is an excellent electromagnetic wave (EMW) absorber with excellent electrical conductivity and abundant surface functional groups. In this research, Ti₃C₂T_x/TiO₂/PANI multi-layer composites were successfully synthesized by HCl and LiF etching, one-step hydrothermal method and in-situ polymerization. Ti₃C₂T_x 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 Ti₃C₂T_x through hydrothermal reaction enhances the interface polarization, and then polyaniline (PANI) is doped on the surface of Ti₃C₂T_x where TiO₂ particles are grown by in-situ polymerization. Due to the excellent dielectric properties and synergistic effects of the material itself, Ti₃C₂T_x/TiO₂/PANI composites have excellent EMW absorption property. In this study, the Ti₃C₂T_x/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 < -10 dB) of 5.92 GHz (11.84 GHz to 17.76 GHz) at 2.10 mm. The results show that the Ti₃C₂T_x/TiO₂/PANI composites are expected to become EMW absorber with thin thickness and high absorption strength.