0D Fe3O4 Nanoparticles Anchored on 2D Layered Double Hydroxides: A Composite Structure for Enhanced Microwave Absorption and Corrosion Protection

To meet the stealth needs of submarines at sea, researchers have developed wave-absorbing coatings. However, the marine environment tends to corrode the coatings and affect their performance. Therefore, it is necessary to develop materials with both wave-absorbing and anti-corrosion functions. In this study, we developed Fe 3 O 4 /LDHs composite with enhanced microwave absorption properties by uniformly anchoring Fe 3 O 4 particles onto the surface of hexagonal MgAl-layered double hydroxides (LDHs) through one-step hydrothermal and hot-solvent methods. The even dispersion of Fe 3 O 4 mitigates nanoparticle agglomeration and promotes synergistic effects between the magnetic and dielectric components, significantly boosting magnetic loss. The composite achieved a minimum reflection loss (RL min ) of −53.46 dB, nearly double that of pure Fe 3 O 4 (−27.31 dB), while maintaining the same effective absorption bandwidth (EAB). Moreover, the Fe 3 O 4 /LDHs demonstrate excellent dispersion ability in epoxy (EP). The resistance to corrosion of Fe 3 O 4 /LDHs@EP is significantly enhanced, shown by the low-frequency impedance modulus, which stays above 10 11 Ω cm 2 even after 19 days of immersion, which was four orders of magnitude higher than that of the pure Fe 3 O 4 @EP coatings (10 7 Ω cm 2 ). The Fe 3 O 4 /LDHs composite material exhibits dual capabilities of stealth and anti-corrosion, providing valuable insights for the development of marine stealth technologies. Graphical Dual function microwave absorption-corrosion protection of Fe 3 O 4 /LDHs composite coatings.