Protection of ZnMgAl coated steel corrosion by cerium gluconate in 0.05 M NaCl solution

The application of inhibitor as an efficient method to protect Zn Mg Al (ZMA) coated steel is first reported in this work. The inhibition performances of newly synthesized cerium gluconate (CG) for ZMA coated steel in 0.05 M NaCl solution were investigated by scanning electron microscopy (SEM), X-ray photoelectron spectroscope (XPS), electrochemical impedance spectroscopy (EIS) measurements, potentiodynamic polarization (PDP) measurements and neutral salt spray (NSS). The synthesized CG exhibits excellent inhibition efficiency of 98.4% at 200 ppm, which is much better than the individual or combined use of sodium gluconate (SG) and cerium (III) nitrate hexahydrate (CNH). Additionally, CG shows long-term protection for ZMA coated steel. A synergistic inhibition model between Ce oxide/hydroxide precipitation with CG adsorption film is proposed based on the obtained results. This work offers a promising option for the corrosion protection of ZMA coated steel.