Coupling dielectric and magnetic components on a ternary composite for enhancing impedance matching and microwave absorption

Here in, a novel ternary manganese monoxide@nitrogen-doped carbon nanotube@cobalt composite was obtained via a scalable multistep reaction pathway. Mnganese monoxide (MnO) is adopted as the microwave transparent substrate to couple dielectric and magnetic components. The abundant internal voids of MnO and numerous interfaces between MnO and carbon can increase the dielectric loss to improve the microwave absorption (MA) performance, metal cobalt is employed as the magnetic component to enhance the magnetic loss. Benefiting from the synergistic effect of heterostructures, the ternary absorber exhibits the minimum reflection loss (RLmin) of −48.65 dB@8.1 GHz@2.8 mm and the effective absorption band (EAB) of 5.8 GHz with the thickness of 1.7 mm. Furthermore, the crystal structure, material components, surface element distribution and magnetic properties of the absorbers are characterized, the structure-performance correlation between “Physical properties” and “Electromagnetic performance” is established. Finally, the reliable MA mechanism based on “hierarchical component modulation” is summarized to guide the design of MnO-based absorbers.