Core-shell Co-doped NiFe LDH@SiCnw nanocomposite towards efficiency microwave absorption with corrosion resistance

The harsh marine environment demands enhanced corrosion resistance and compatibility of wave-absorbing materials for ship platforms. Urgently required are wave-absorbing composites with both efficient performance and corrosion resistance. In this work, a core–shell composite NiCoFe LDH@SiCnw was specifically designed and synthesized using a one-step hydrothermal in-situ growth method. Through precise tuning of the LDH content on the composite surface, combined with the principle of impedance matching, the dielectric loss is kept within a moderate range. The effective absorption bandwidth (EAB) of LDH2@SiCnw at a thickness of 2.47 mm is as high as 6.19 GHz when the filling ratio is only 3 %. Because the synergistic effect of the porous LDH shell and the core–shell heterostructure to enhance the dielectric loss and multiple scattering absorption of microwave in the composite. Significantly, the LDH2@SiCnw anti-corrosion coating exhibits exceptional long-term corrosion resistance owing to the barrier effect provided by SiCnw and the Cl- inhibition of LDH, the |Z|0.01Hz remains at 7.8 × 109 Ω·cm2 even after 30 days of immersion in 3.5 wt% NaCl solution. Hence, the LDH@SiCnw composites developed in this study hold significant potential in advancing the progress of functionalized MA materials with enhanced corrosion resistance.