Improved Interfacial Interactions by Core–Shell CoFe 2 O 4 @SiO 2 Composites to Enhance the Ability of Corrosion Resistance and Electromagnetic Wave Absorption

Abstract With the rapid development of science and technology, stealth and anti‐corrosion activities in oceans have attracted widespread attention. This study successfully prepares CoFe 2 O 4 @SiO 2 with a core–shell structure. This core–shell structure endows the CoFe 2 O 4 @SiO 2 with good impedance matching and interfacial polarization. Thus, the CoFe 2 O 4 @SiO 2 exhibits an excellent electromagnetic wave absorption performance with a minimum reflection loss of −45.16 dB. Moreover, the CoFe 2 O 4 @SiO 2 exhibits an excellent dispersion ability in epoxy. The corrosion resistance of the CoFe 2 O 4 @SiO 2 /epoxy is enhanced. After 60 days of immersion, the low‐frequency impedance modulus of the CoFe 2 O 4 @SiO 2 /epoxy is still >10 9 Ω cm 2 . The CoFe 2 O 4 @SiO 2 realize the dual functions of stealth and anti‐corrosion, which provide ideas for developing marine stealth applications.