Fabrication and corrosion inhibition behavior of hierarchical Al-Cr co-doped magnesium ferrites nanomaterial for steel

Abstract Approximately 85% of commercially used steel is carbon steel, which is more vulnerable to galvanic, and natural corrosion and nanomaterials have a wide range of electrochemical applications as corrosion inhibitors. The present study demonstrated the fabrication of magnesium ferrite and its Al-Cr co-doped derivatives; MgAlxCrxFe2-2xO4 (x = 0.0, 0.1, 0.3, 0.5) by urea assisted polymeric citrate route combustion method. The structure, topographical features and elemental composition of all the prepared samples were analyzed using X-ray diffraction and scanning electron microscopy. The electrochemical impedance spectroscopy was used to investigate the anticorrosion behavior of the thin coating of prepared nanomaterials for carbon steel in an acidic medium. Electrochemical impedance measurements revealed the monolayer formation of nanomaterials on the steel surface, which is effective in protecting the steel from oxidation. It enhanced the blockage of the pathway for water and oxygen to react with iron to form iron oxide. The MgAl0.5Cr0.5FeO4 exhibited the highest corrosion inhibition efficiency among the prepared samples with charge transfer resistance of 27 kΩ. The 0.025 g/L of nanomaterial dosage and 2 h of immersion time are appropriate for better corrosion resistance.