Computational and electrochemical investigation for corrosion inhibition of nickel in molar nitric acid by piperidines
Khaled, K. F.; Amin, Mohammed A.;
Abstract
The adsorption and corrosion inhibition behaviour of four selected piperidine derivatives, namely piperidine (pip), 2-methylpiperidine (2mp), 3-methylpiperidine (3mp), and 4-methylpiperidine (4mp) at nickel in 1.0 M HNO3 solution were studied computationally by the molecular dynamics simulation and quantum chemical calculations and electrochemically by Tafel and impedance methods. The results indicate a strong dependence of the inhibition performance on the nature of the metal surface, in addition to the structural effects of piperidines. Inhibition is accomplished by adsorption of piperidines on the metal surface without detectable changes in the chemistry of corrosion. Adsorption is predominantly chemisorptive in the active region and by hydrogen bond formation in the passive region. The potential of zero charge (PZC) of the nickel electrode was determined in 1.0 M HNO3 solutions in the absence and presence of 10-2 M 2mp, and the electrostatic (physical) adsorption was discussed. The inhibition efficiency of these compounds increases in the order: 4mp > 3mp > 2mp > pip. Molecular simulation studies were applied to optimize the adsorption structures of piperidine derivatives. The nickel/inhibitor/solvent interfaces were simulated and the charges on the inhibitor molecules as well as their structural parameters were calculated in the presence of solvent effects. Quantum chemical calculations based on the ab initio method were performed to determine the relationship between the molecular structure of piperidines and their inhibition efficiency. Results obtained from Tafel and impedance methods are in good agreement and confirm theoretical studies. © 2008 Springer Science+Business Media B.V.
Other data
Title | Computational and electrochemical investigation for corrosion inhibition of nickel in molar nitric acid by piperidines | Authors | Khaled, K. F. ; Amin, Mohammed A. | Keywords | Acid corrosion inhibition;Impedance;Molecular adsorption;Molecular dynamic simulation;Quantum chemical calculations | Issue Date | 1-Nov-2008 | Publisher | SPRINGER | Journal | Journal of Applied Electrochemistry | ISSN | 0021891X | DOI | 10.1007/s10800-008-9604-5 | Scopus ID | 2-s2.0-54149102235 | Web of science ID | WOS:000260008700016 |
Recommend this item
Similar Items from Core Recommender Database
Items in Ain Shams Scholar are protected by copyright, with all rights reserved, unless otherwise indicated.