Hollow engineering of core–shell Fe₃O₄@MoS₂ microspheres with controllable interior toward optimized electromagnetic attenuation

The development of electromagnetic wave absorbing materials with wideband absorption and thin thickness confronts huge challenges in addressing the aggravating problem of electromagnetic pollution. Herein, hollow core–shell Fe₃O₄@MoS₂ microspheres with controllable interior and tunable shell are constructed to precisely regulate the electromagnetic wave attenuation. The results demonstrate that hollow Fe₃O₄ microspheres exhibit strong absorption in C–X bands owing to their strong ferromagnetic resonance. By structural regulation, hollow core–shell Fe₃O₄@MoS₂ microspheres not only ensure superior electromagnetic wave absorption intensity at thin thickness, but also endow wideband absorption. Benefiting from the cooperative merits of manipulated Fe₃O₄ interior and controllable MoS₂ shells, the as-synthesized microspheres display obvious interface polarization, defect/dipole polarization, and multiple scatterings, thereby resulting in ameliorated impedance matching and outstanding attenuation performance. Especially for Fe₃O₄@MoS₂-2, the minimum reflection loss is − 69.01 dB at 2.66 mm and the effective absorption bandwidth reaches 8.40 GHz when the thickness is 3.0 mm. This study systematically investigates the balance relationships between core–shell structures and absorption attenuation, and simultaneously provides a referable strategy to modulate the electromagnetic wave absorption by structural optimization.