Abstract Copper corrosion inhibition in 1M nitric acid solution using Doxycycline has been studied by mass loss method and DFT calculations. It was found that this compound acts as a good inhibitor for copper corrosion in the acid solution (the inhibition efficiency is 95.65% at T= 308K and C =10-3M). The inhibiting action of Doxycycline (DXC) was discussed in view of its adsorption on the metal surface. The adsorption was found to be spontaneous and follows the modified Langmuir adsorption isotherm known as Villamil’s isotherm. The results show that the inhibition efficiency IE (%) increases with increasing concentration in the studied molecule, but decreases slightly with increasing temperature. The thermodynamic adsorption and activation functions were also determined and discussed. Quantum chemical calculations at B3LYP/6-31G (d) level was further used to determine molecular parameters in order to ascertain any correlation between the inhibition efficiency and the molecular structure.
Keyword: Corrosion inhibition, Mass loss method, DFT calculations, Inhibition efficiency, Molecular descriptors.