Interface Engineering of Heterogeneous NiSe₂-CoSe₂@C@MoSe₂ for High-Efficient Electromagnetic Wave Absorption

Optimization of components and micromorphology regulation are shown to be effective in boosting electromagnetic wave absorption (EMWA). One approach to achieve this enhancement is by utilizing the polarization effects of heterogeneous interfaces. Herein, NiSe2-CoSe2@C@MoSe2 composites derived from NiCo-MOF-74 are fabricated via a facile selenization reaction and subsequent hydrothermal method. By varying the mass ratios of NiSe2-CoSe2@C and MoSe2, a series of NiSe2-CoSe2@C@MoSe2 composites with hierarchical flower-like core-shell structures are obtained. The EMWA properties of the composites display a trend of initially increasing and then decreasing with the increasing content of MoSe2. Interestingly, when the mass ratio of NiSe2-CoSe2@C and MoSe2 is 3:2, the minimum reflection loss (RL) value is -50.10 dB and an effective absorption bandwidth (RL< -10 dB) value can reach 4.80 GHz (13.20-18.00 GHz). The remarkable EMWA capability can be ascribed to the synergy effects of conductive loss, polarization loss, and suitable impedance matching. This work establishes a new pathway for the synthesis of transition metal dichalcogenides-based composites, which hold great promise as high-performance materials for EMWA applications.