Electrochemical Investigations of Pyridine-2-Carbaldehyde Derivatives as Potential Inhibitors against Copper Corrosion in 0.1M HNO3


  • Sini Varghese C Department of Chemistry, St. Joseph’s College (Autonomous), Irinjalakuda
  • Joby Thomas K Department of Chemistry, St. Thomas College (Autonomous), Thrissur https://orcid.org/0000-0002-2782-0418


Corrosion inhibitors, Isotherm, pyridine-2-carbaldehyde, El-Awady, Langmuir


The corrosion inhibition efficiency of Pyridine-2-carbaldehyde-2-aminobenzoic acid (2PC2ABA) and Pyridine-2-carbaldehyde-3-aminobenzoic acid (2PC3ABA) on copper in 0.1M HNO3 solution has been investigated and compared using electrochemical impedance spectroscopy, adsorption studies and potentiodynamic polarization analysis. The pyridine-2- carbaldehyde derivatives exhibited very good corrosion inhibition on copper in HNO3 medium and the inhibition efficiency increased with the increase in concentration of the inhibitor. The adsorption of the inhibitor on the surface of the corroding metal obeys Langmuir and El-Awady adsorption isotherm for 2PC2ABA and 2PC3ABA respectively. Thermodynamic parameters (Kads, ΔG0ads) were calculated using adsorption isotherm. Polarization studies revealed that both compound act as a mixed type inhibitor.