Calcination Mass Synthesis and Excellent Anticorrosion Performance of <i>X</i> -SrZn ₂ (PO ₄ ) ₂ ( <i>X</i> = Mn, Fe, and Co) Magnetic Materials with Multilayer Lamellar Structures

Investigating magnetic metal doping in high-temperature anticorrosion materials is both crucial and complex. In this study, X-SrZn2(PO4)2(X-SZP) (X = Mn, Fe, Co) was synthesized via high-temperature mass calcination to create dilute magnetic materials with enhanced high-temperature resistance and stability. The doping of Mn, Fe, and Co elements introduces dilute magnetic properties that alter electron movement paths in corrosion reactions through the Lorentz force, thereby impeding charge transport and slowing the corrosion process. The electron conduction band of the doped X-SZP is significantly lower than the standard electrode potential of Fe2+/Fe, providing superior cathodic protection. Upon exposure to corrosive environments, X-SZP dissociates, releasing Zn2+, Sr2+, and Mn2+/Fe2+/Co2+ ions, which provide polycationic passivation. The combined effects of magnetically induced anodic electron deflection, electrochemical cathodic protection, multilayer lamellar structure shielding, and multication passivation significantly enhance the corrosion resistance of the X-SZP coatings. Electrochemical tests show that the corrosion resistance of Fe-SZP is 3.50 times higher than that of epoxy resin and 1.24 times higher than that of SZP shielding layers. This study presents an approach to designing efficient corrosion-resistant materials, offering broad prospects in corrosion inhibition.