Surface Size- and Structure-Optimized Design of Two-Dimensional MXene Nanosheets for Electromagnetic Wave Absorption

As a two-dimensional material, Ti(3)C(2)Tx-Mxenenanomaterial has been extensively studied for its applications inelectromagnetic wave absorption (EMI) due to its extremely high surfacearea, excellent hydrophilicity, and metallic-like conductivity. However,the surface size and sandwich structure of two-dimensional (2D) MXenenanomaterials are the key factors affecting their absorption properties,but no studies have been carried out. Therefore, in this work, a singlelayer of Ti(3)C(2)Tx-Mxene nanosheet material isfabricated by modification and its physical properties are characterizedand analyzed. Then, the absorption properties of monolayers Ti(3)C(2)Tx-Mxene nanomaterials with different surfacesizes are investigated both by numerical simulations and experiments,respectively, and surface sizes are optimized by orthogonal tests.Finally, the interlayered two-dimensional Ti(3)C(2)Tx-Mxene nanomaterials are optimized by particle swarm optimization(PSO) algorithm based on nanometer and millimeter size space. Theresults show that the best wave absorption performance is achievedwith a surface size of 0.8 & mu;m length and 0.6 & mu;m width,resulting in a reflectivity of -98.59 dB. When ethanol is usedas the matching material in the middle layer, the sandwich structurehas better absorption properties than the air layer. The reflectivityof the PSO-optimized 2D Ti(3)C(2)Tx-Mxene sandwichstructure in the nanometer size is observed in the range of -109.58to -90.43 dB in the frequency range of 2-18 GHz. Inaddition, the reflectivity on the millimeter size fluctuates between-2.9 and -28.86 dB in the frequency range of 2-18GHz, and the effective absorption bandwidth reaches 7.21 GHz. Theoptimized material shows the characteristics of low reflectivity andwide effective absorption frequency band, indicating that the optimizedsurface size and sandwich structure can better enable Ti(3)C(2)Tx-Mxene nanosheets to be applied to ethylene methylacrylate (EMA) materials.