Enhanced microwave-absorbing performances for phthalocyanine/MXene nanocomposites by constructing oxygen vacancies

In order to alleviate the growing problem of electromagnetic radiation pollution, it is both urgent and challenging to develop electromagnetic wave absorbing materials with strong absorption and wide effective absorption bandwidth (EAB). The structural design of heterojunction surfaces plays an important role in the development of advanced microwave absorbing materials. Building on this concept, three-dimensional nanocomposites Alk-Ti₃C₂T_x/nitro metal phthalocyanine (TNMP) with phthalocyanine derivative NMP-MXene are designed. TNMP composites are prepared by self-assembly of surface hydroxylated treated MXene with floral spherical nitrophthalocyanine. This method effectively constructs rich heterojunction surfaces and induces dipole polarization effect by designing a large number of oxygen vacancies through coordination, which effectively enhances the material attenuation capability while balancing impedance matching characteristics. By modulating the metal centers in the NMP, the coordination mode of the heterojunction surfaces is regulated, and the polarization relaxation loss is improved to achieve excellent electromagnetic wave absorption performance (reflection loss (RL) of −62.12 dB at a thickness of 1.25 mm). And based on the bionic structure design, a unit cycle structure of double-layered butterfly wing skeleton (DLBWS) is constructed to obtain an ultra-wideband electromagnetic wave absorber with an EAB of 12.5 GHz. This research demonstrates a regulatory scheme to elucidate the dipole polarization mechanism and proposes a new method for designing functional materials in ultra-broadband electromagnetic wave absorption.