Preparation of Three-Dimensional Mo2C/NC@MXene and Its Efficient Electromagnetic Absorption Properties

The positively charged MoO3/PDA microspheres are obtained by stacking and assembly of the sheet structure, and the negatively charged MXene nanosheets are wrapped on the surface through the principle of electrostatic self-assembly. After annealing, a nitrogen-doped carbon composite and a MXene-coated Mo2C wave absorber are obtained. The formation of the wrinkled surface provides a complex pore structure, and the multiple interface reflections between the nanosheets enhance the absorption performance. The existence of heterogeneous interfaces and the uneven distribution of space charges accumulated between the interfaces effectively reduce the minimum reflection loss (RLmin). This work explores the effects of the ratio between MoO3/PDA and MXene nanosheets and loading amount on the microwave absorption properties. Mo2C/NC@MXene-2 obtained when the ratio of the two is 3:1 has the best absorption performance under 25% loading. The RLmin is -59.36 dB, and the corresponding effective absorption bandwidth (EAB) is 4.6 GHz at 2.5 mm. This work expands the new applications of MXene-based and Mo2C-based materials and has a guiding significance for the design of electrostatic self-assembly materials.

Automated summary

In this study, positively charged MoO3/PDA microspheres and negatively charged MXene nanosheets wrapped on the surface were obtained using the principle of electrostatic self-assembly. The effects of the ratio between MoO3/PDA and MXene nanosheets and loading amount on microwave absorption properties were investigated. The Mo2C/NC@MXene-2 sample obtained at a ratio of 3:1 and 25% loading showed the best absorption performance.