Study On Fabricate And Electromagnetic Wave Absorption Properties Of Ti₃C₂T_x/Co-based Composites

Recently,electromagnetic wave absorbing materials have attracted more and more attention in the fields of anti-electromagnetic interference,anti-electromagnetic radiation and military stealth.It has become an urgent need to design and develop electromagnetic wave absorbers with strong absorption,wide bandwidth,thin thickness and light weight.As a representative two-dimensional layered material,Ti₃C₂T_x has been widely used in the field of electromagnetic wave absorption due to the ideal conductivity,suitable specific surface area and structural tunability.Meanwhile,metal Co and its oxides have become a stable source of magnetic loss due to their excellent magnetic properties.In this paper,Ti₃C₂T_x/Co-based composites are taken as the research object,and a series of electromagnetic wave absorbers with excellent performance are designed and prepared from the perspective of microstructure control.The main conclusions are as follows:（1）Ti₃C₂T_x/Co nanosheet composites were obtained by solvothermal and electrostatic self-assembly methods.After optimizing the content of Co nanosheets,the layered Ti₃C₂T_x were firmly combined with electrostatic attraction and exhibits ideal electromagnetic wave absorption performance.Specifically,under the synergistic effect of enhanced interfacial polarization,dipole polarization and magnetic loss,the performance of the composite absorber were greatly improved compared to the pure Co and Ti₃C₂T_x.When the matching thickness of the absorber was 3.67 mm,the optimal reflection loss achieve-47.09 d B,and the effective absorption bandwidth reache 2.76GHz.（2）Based on the above research,in order to solve the limitation of high reflection loss,the magnetic component Ni was continued to be introduced,and Ti₃C₂T_x/Co Ni composites were obtained by solvothermal and electrostatic self-assembly methods.The results of scanning electron microscopy showed that the nanosheet Co Ni were firmly anchored on the surface of layered Ti₃C₂T_x due to electrostatic attraction.Owing to the enhanced magnetic loss,the performance of the composite absorber were greatly improved compared to the single component absorber.Specifically,the optimal reflection loss reaches-56.81 d B,and the effective absorption bandwidth achieves 4.08 GHz,which successfully reduces the reflection loss and increases the absorption bandwidth.（3）In order to further reduce the reflection loss and improve the absorption performance,one-dimensional Co₃O₄nanochains were designed and prepared,which were firmly anchored on the surface of two-dimensional layered Ti₃C₂T_x under electrostatic interaction to construct Ti₃C₂T_x/Co₃O₄ composites.One-dimensional Co₃O₄nanochains with shape anisotropy not only provide more electron transition paths,but also form a three-dimensional conductive network.Therefore,Ti₃C₂T_x/Co₃O₄ nanochains exhibit excellent electromagnetic wave absorption performance under the synergistic effect of enhanced interfacial polarization and magnetic loss.At 9.52 GHz,the optimal reflection loss of the absorber reaches-60.06 d B,achieving the goal of low reflection loss.（4）To further break through the limitation of the thickness of the above absorbers,hollow CoS microspheres were synthesized by solvothermal method and adsorbed on the surface of two-dimensional Ti₃C₂T_x under electrostatic action.The unique hollow structure of CoS is beneficial to improve impedance matching.Simultaneously,the electromagnetic absorption performance of the composite absorbers have been significantly improved under the synergistic effect of various loss mechanisms such as interfacial polarization,dipole polarization and ferromagnetic resonance.Specifically,when the absorber matching thickness achieves 1.81 mm,the optimal reflection loss reaches-60.28 d B at 12.24 GHz,which successfully achieves the expectation of thin thickness and strong absorption.Figure[52]Table[5]References[126]...