Inhibition Effect of Atenolol on Copper Corrosion in 1M HNO3: Experimental Study and DFT

Abstract

Atenolol was examined as a copper corrosion inhibitor in 1M nitric acid solution using the mass loss technique and quantum chemical studies, based on density functional theory (DFT) at the B3LYP level with the base 6-311G (d,p). The inhibitory efficiency of the molecule increases with increasing concentration and temperature. The adsorption of the molecule on the copper surface follows the modified Langmuir model. The thermodynamic quantities of adsorption and activation were determined and discussed. The calculated quantum chemical parameters related to the inhibition efficiency are the energy of the highest occupied molecular orbital E(HOMO), the energy of the lowest unoccupied molecular orbital E(LUMO), the HOMO-LUMO energy gap, the hardness (η), softness (S), dipole moment (μ), electron affinity (A), ionization energy (I), absolute electronegativity (χ),absolute electronegativity (χ), fraction (ΔN) of electrons transferred from Atenolol to copper and electrophilicity index(ω). The local reactivity was analyzed through the condensed Fukui function and condensed softness indices to determine the nucleophilic and electrophilic attack sites. There is good agreement between the experimental and theoretical results.

Study of the Thermodynamic Quantities of Adsorption and Activation of Piroxicam in Copper Corrosion in a Nitric Acid Environment

“…The mass loss method [11][12][13] is one of the most widely used methods for evaluating corrosion inhibition of metals due to its simplicity and reliability of measurements. Mass loss measurements were made by total immersion of the pre-weighed copper sample in 100ml capacity beakers containing 50ml of the test solution maintained at a temperature of (298K to 323K).…”