Anion-substitution interfacial engineering to construct C@MoS₂ hierarchical nanocomposites for broadband...

Developing an effective strategy to regulate the interfacial properties of hierarchical structure is of great significance for preparation of high-performance electromagnetic wave absorption (EMA) materials. Ion-substitution can change intrinsic structure and properties of a materials, but its effect on the interfacial properties of hierarchical structure remained to be explored. Herein, we first constructed a C@MoS₂ hierarchical structure via simple hydrothermal reaction, then used the ion-substitution strategy to replace the S atoms in MoS₂ with O, F and Se, and finally obtained anion-substituted hierarchical structure (C@X-MoS₂, X = O, F, Se). The results show that ion-substitution destroys the MoS₂ crystal structure and realizes tunable dielectric properties of C@MoS₂, which leads to further enhancement of overall interfacial polarization. After optimization, the absorption strength and width of C@O-MoS₂ has been significantly improved. The minimum reflection loss (RL_min) reaches -62.17 dB, and the maximum effective absorption bandwidth (EAB_max) is 7.0 GHz. The simulation results show the obtained absorbent can greatly reduce the radar cross section of target, indicating it has broad application potential. Therefore, this work provides a novel method for regulation of EMA performance of hierarchical structure and preparation of high-performance absorbents.