Article 2025 · 3 citations

Fabrication of metal-organic gel (MOG) nanoparticles-enhanced epoxy coating as a pH-sensitive corrosion inhibitor under diverse environmental conditions

Oroujzadeh, Amir Reza, Nematollahzadeh, Ali, Dabaleh, Amin, Seifzadeh, Davod, Shojaei, Akbar

Abstract

Incorporating rigid nanoparticles into epoxy resins enhances anti-corrosion coatings. Still, it often suffers from limited defect-filling ability due to its inherent rigidity, resulting in suboptimal performance under harsh thermophysical and variable pH conditions. This experimental study investigates the effect of metal-organic gel (MOG) nanoparticles as flexible amorphous gels on enhancing the corrosion resistance of epoxy coatings, with a particular focus on the influence of pH. To achieve this, we synthesized an environmentally friendly zirconium-based metal-organic gel (Zr-MOG) nanostructure at various aging temperatures. Characterization techniques were employed to analyze the morphology and structure of Zr-MOGs, confirming the successful synthesis of meso-microporous amorphous xerogels. The pH sensitivity of optimized Zr-MOG nanoparticles (aged at 140 degrees C) was evaluated in a 3.5 % NaCl solution. The results indicated variations in surface charge formation under various environmental conditions. The active corrosion protection (self-healing) properties of the coatings were assessed via electrochemical impedance spectroscopy (EIS) at various immersion times. The healing efficiency of Zr-MOG-modified epoxy at acidic, neutral, and alkaline pH levels after 24 h was measured to be 472.7 %, 287.8 %, and 208.8 %, respectively, suggesting very efficient corrosion protection at various pH values. Furthermore, field emission scanning electron microscopy (FE-SEM) images of the scratched coating regions confirmed that the Zr-MOG nanoparticle-modified coating (Ep/Zr-MOG-pH-3) exhibited excellent performance in an acidic environment. However, the highest corrosion resistance was exhibited by Ep/Zr-MOG-pH-7, with an impedance value of similar to 260 k Omega cm(2). These findings demonstrate the potential of Zr-MOG nanoparticles to improve the performance of epoxy coatings in corrosive conditions.

Keywords

Metal-organic gel Self-healing pH-sensitive corrosion inhibitor Smart epoxy coating Harsh electrolytes NANOCOMPOSITE STEEL PERFORMANCE PROTECTION SURFACE

WoS Categories

Chemistry, Applied Materials Science, Coatings & Films

Citation

Journal: PROGRESS IN ORGANIC COATINGS
Year: 2025
Volume: 209
ISSN: 0300-9440
eISSN: 1873-331X
DOI: 10.1016/j.porgcoat.2025.109621
WoS UID: WOS:001566712700001

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