Broadband Microwave Absorption in MoS2–Co Nanocomposites by the Synergy of Dielectric and Magnetic Losses

Abstract

The development of lightweight materials with high microwave absorption efficiency is critical for advanced stealth and electromagnetic interference applications. Hybrid composites that integrate dielectric and magnetic components offer enhanced attenuation by leveraging multiple loss mechanisms. To explore this potential, we decorated MoS₂ particles with magnetic Co nanoparticles (Co content ranging from 5–20 wt.%) and systematically investigated their microwave absorption properties over the 2–18 GHz frequency range. The individual materials and hybrid structures were synthesized using a multi-step strategy involving solution-based methods such as hydrothermal synthesis, chemical reduction of reactants, and sonication. Structural, morphological, compositional, and magnetic analyses collectively confirmed the successful incorporation and uniform dispersion of Co within the nanosheets of MoS2 host. Meanwhile, the microwave absorption properties revealed a strong dependence on Co content. Notably, the nanocomposite containing 15 wt.% Co exhibited superior performance, achieving a minimum reflection loss of −17.17 dB at 13.84 GHz and an ultra-broad effective absorption bandwidth of 7.51 GHz. This performance is attributed to synergy between the dielectric, magnetic, and morphologically derived mechanisms. Further, the hybrid design enables tunable interactions with incident waves, facilitating broad frequency coverage and enhanced attenuation. Overall, this work demonstrates the effectiveness of MoS2–Co nanocomposites and their compatibility with advanced stealth and microwave absorption applications in this frequency range.