Dipole Polarization and Synchronous Magnetic Modulation Induced by FeN4 Moiety on Ti3C2Tx for Superior Electromagnetic Wave Absorption Performance

Abstract

Polarization-dependent loss is important to the highly electromagnetic wave absorption (EWA) performance. Recently, metal–N_x moieties have been discovered to trigger polarization loss, but the physical origin and other possible related loss mechanisms still need to be deeply explored. In this article, we reveal that the FeN₄ moiety from iron phthalocyanine (FePc) can coordinate with Ti₃C₂T_x through Ti–OH groups, inducing dipole polarization and synchronous magnetic modulation in Fe/TiO₂/Ti₃C₂T_x composites. Interestingly, using the enhanced electric dipole moment and increased number of unpaired electrons in Fe atoms, the dipole polarization loss and possible magnetic response can be rapidly confirmed and evaluated. As a result, the minimum reflection loss (RL_min) of Fe/TiO₂/Ti₃C₂T_x composites reaches −67.12 dB at 6.72 GHz with a thickness of 3.32 mm. This study elaborates the EWA mechanism based on the atomic scale, and provides a new idea to design efficient EWA materials.