Abstract
Copper corrosion inhibition in 1 M HNO3 solution by some benzotriazole derivatives, namely N-(2-thiazolyl)-1H-benzotriazole-1-carbothioamide (TBC), N-(furan-2-ylmethyl)-1H-benzotriazole-1-carbothioamide (FBC) and N-benzyl-1H-benzotriazole-1-carbothioamide (BBC), was investigated by ac impedance, dc polarization and weight loss techniques. A significant decrease in the corrosion rate of copper was observed in presence of the investigated compounds. The corrosion rate was found to depend on the concentration and type of the inhibitor. The degree of surface coverage of the adsorbed inhibitor was determined by weight loss technique, and it was found that the results obeyed Langmuir adsorption isotherm. Tafel polarization data indicated that the three selected inhibitors were of mixed type. The reactivities of the compounds under investigation were analyzed through Fukui indices, derived from density functional theory (DFT), to explain their inhibition performance.