Double-carbon hierarchical engineering toward hetero-interfaces induced polarization and defect excitation

Abstract

A key strategy for achieving effective electromagnetic wave (EMW) absorption in multicomponent composites involves rational structural design and elemental doping. Here, a hybrid MoSe₂/NiSe₂@C@PC absorber with multiple heterogeneous interfaces is fabricated using a simple hydrothermal method followed by high-temperature pyrolysis. Density-functional theory reveals that the differences in work function among the different components facilitate the successful construction of multiple heterostructures, specifically MoSe₂/NiSe₂, NiSe₂/C, and MoSe₂/C. Additionally, the calculated differential charge density (DCD) further describes the inhomogeneous distribution of space charge at the heterojunctions and highlights the pronounced heterogeneous interfacial polarization in MoSe₂/NiSe₂@C@PC. Notably, the defects induced by Se doping in the hybrid serve as polarization centers, enhancing dipolar polarization and thereby promoting the dissipation of EMW energy. Thanks to the outstanding component design of MoSe₂/NiSe₂@C@PC, it not only demonstrates favorable microwave absorption performance but also retains superior stability in simulated seawater, enhancing its corrosion resistance. Specifically, MoSe₂/NiSe₂@C@PC achieves a minimum reflection loss (RL_min) of −55.1 dB at 2.4 mm and an effective absorption bandwidth (EAB) of up to 6.0 GHz at 2 mm. In practical military stealth technology, MoSe₂/NiSe₂@C@PC exhibits remarkable potential, as evidenced by radar cross-section calculations. This research illustrates a feasible multi-heterostructure design and the incorporation of polarization elements in magnetoelectric composites for effective EMW absorption.