Electrochemical, Theoretical, and Surface Morphological Studies of Corrosion Inhibition Effect of Green Naphthyridine Derivatives on Mild Steel in Hydrochloric Acid

By Priyanka Singh, E. Ebenso, L. Olasunkanmi, I. Obot, M. Quraishi. 2016

303 citations recorded by the source corpus.

The corrosion inhibition efficiencies of three novel naphthyridines namely, 5-amino-9-hydroxy-2-phenylchromeno[4,3,2-de][1,6]naphthyridine-4-carbonitrile (N-1), 5-amino-9-hydroxy-2-(p-tolyl)chromeno[4,3,2-de][1,6]naphthyridine-4-carbonitrile (N-2), and 5-amino-9-hydroxy-2-(4-methoxyphenyl)chromeno[4,3,2-de][1,6]naphthyridine-4-carbonitrile (N-3) have been investigated for mild steel in 1 M HCl solution by using weight loss, electrochemical impedance spectroscopy, and potentiodynamic polarization methods. All three compounds show high inhibition activities at 6.54 × 10–5 M : N-1, 94.28%; N-2, 96.66%; and N-3, 98.09%. Electrochemical impedance spectroscopy analysis reveals an increase in polarization resistance due to the adsorbed inhibitor molecules on metal surface. Potentiodynamic polarization analysis reveals that all three compounds act as mixed-type inhibitors but of predominantly cathodic type. The adsorption of the studied compounds on mild steel surface follows the Langmuir adsorption isotherm. Sur...

Subfields: Civil and Structural Engineering, Electrochemistry, Materials Chemistry

View Paper: https://www.semanticscholar.org/paper/0399a9418d99b31412cfb892fcbbfd47d0f39584