Corrosion inhibition of copper in nitric acid solutions using a new triazole derivative

Abstract

In this study, the inhibition effect of 3-amino-1,2,4-triazole (ATA) on copper corrosion in 2M HNO 3 solution was studied. Electrochemical techniques such as potentiodynamic polarization curves, weight loss (WL) and electrochemical impedance spectroscopy (EIS) were used. Results showed that ATA has good inhibition efficiency on the corrosion of copper in 2M HNO 3 solution. Polarization measurements indicated that, the studied inhibitor acts as a mixed type one. The inhibition efficiency depends on the concentration of inhibitor and reaches 82.2% at 10 -2 M ATA. The results obtained from the different methods are in good agreement. The adsorption of ATA molecules on the copper surface obeys Langmuir adsorption isotherm. The adsorption free energy of ATA on copper (-29.95 kJ/mol) reveals a physical adsorption of the inhibition on the metal surface. Quantum chemical calculations using DFT at the B3LYP/6-31G* level of theory was further used to calculate some electronic properties of the molecule in order to ascertain any correlation between the inhibitive effect and molecular structure of 3-amino-1,2,4-triazole. © 2012 by ESG.