Corrosion Inhibition Performance of 3,5-Diamino-1,2,4-triazole for Protection of Copper in Nitric Acid Solution

The 3,5-diamino-1,2,4-triazole (DAT) is investigated as corrosion inhibitor for copper in 2 M HNO3 medium by electrochemical techniques such as electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization curves and weight loss measurements. Results show that DAT is a good corrosion inhibitor and its inhibition efficiency increases by increasing the inhibitor concentration. Changes in impedance parameters were indicative of adsorption of DAT on the copper surface, leading to the formation of protective films. Tafel polarization study revealed that DAT acts as a mixed type inhibitor. The inhibitor adsorption process in copper/DAT/nitric acid system was studied at different temperatures (303-343 K) by means of weight loss measurements. The adsorption of DAT on copper surface obeyed Langmuir’s adsorption isotherm. The kinetic and thermodynamic parameters for copper corrosion and inhibitor adsorption, respectively, were determined and discussed.