Electrochemical And Quantum Chemical Studies Of The Corrosion And Hydrogen Evolution Reaction Of Mild Steel

7639 Words Jun 4th, 2016 31 Pages
Electrochemical and quantum chemical studies of the corrosion and hydrogen evolution reaction of mild steel in acid medium
Rabab M. El-Sherif a,*, K. M. Zohdy b Sowmya Ramkumar c

a Cairo University, Faculty of Science, Department of chemistry, Giza, 12613, Egypt b Higher Technological Institute, 10th of Ramadan City, Egypt c Department of chemistry, PSGR Krishnammal College for Women, Peelamedu, Coimbatore, India

Abstract
Electrochemical behavior and hydrogen evolution reaction of mild steel in sulfuric acid solutions, containing different concentrations of gamma-Aminobutyric acid (GABA) as a green inhibitor have been investigated. The electrochemical techniques included Tafel polarization and electrochemical impedance spectroscopy (EIS). The rate of both the corrosion reaction and the hydrogen evolution affected significantly by changing GABA concentrations. Polarization results showed that GABA is a mixed type inhibitor with good inhibition efficiency. Increasing the temperature led to an increase in the hydrogen evolution rate and a decrease in the total surface resistance value (RT) or the relative film thickness (1/CT) of the steel. Quantum calculation including EHOMO, ELUMO, the energy gap (?E) and the fraction of transferred electrons (?N) demonstrated the inhibition ability of GABA. The results were confirmed by surface examination using scanning electron microscopy. Adsorption of GABA on the steel surface fitted the Langmuir isotherm. Thermodynamic parameters…

More about Electrochemical And Quantum Chemical Studies Of The Corrosion And Hydrogen Evolution Reaction Of Mild Steel

Open Document