Synthesis, characterization and anticorrosion performance of a new corrosion inhibitor based on cobalt- phenanthroline- p-hydroxybenzoic acid ternary complex

In this paper, a new corrosion inhibitor based on cobalt- phenanthroline- p-hydroxybenzoic acid ternary complex was synthesized. Its anti-corrosion effects on carbon steel in 0.5 M HCl were investigated by weight-loss measurements, electrochemical tests, surface analyses, and quantum chemical calculations. The results indicated that the Co-phen-phba ternary complex exhibits excellent anti-corrosion efficiencies of ∼97 % at 298 K and ∼86 % at 328 K. The excellent anti-corrosion performance of Co-phen-phba ternary complex could be attributed to the combination of inorganic and organic corrosion inhibitors. Theoretical calculations established the correlation between the structure and the anti-corrosion effect of corrosion inhibitor.