Investigation of anti-corrosive properties of o-anisidine-N-salicylidene and its nanocomposite o-anisidine-N-salicylidene/NiONPs on mild steel in 2 N HCl

Abstract

This paper describes the inhibition of mild steel corrosion in 2 N HCl aqueous solution byo-anisidine-N-salicylidene (o-AnNS) and o-AnNS assembled on nickel oxide nanoparticles (NiONPs), which was investigated using three techniques: weight loss, electrochemical impedance spectroscopy (EIS), and galvanostatic polarization. Furthermore, characterization of the synthesized products was performed via proton nuclear magnetic resonance (¹H NMR), transmission electron microscopy (TEM), dynamic light scattering (DLS), Fourier transform infrared (FTIR) spectroscopy, powder X-ray diffraction (PXRD), mass spectrometry (ESI-MS), and nuclear magnetic resonance (¹H NMR). Weight loss measurements were performed to study the effect of inhibitor concentration, time and temperature. Electrochemical impedance spectroscopy (EIS) measurements revealed that corrosion inhibition takes place due to the adsorption of inhibitor molecules on the metal surface. Galvanostatic polarization measurements show that both inhibitors act as a mixed-type inhibitor. Adsorption of inhibitors on a mild steel surface obeys the Langmuir adsorption isotherm. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) measurements were carried out to characterize the nature of the corrosion morphology. All the results confirm that o-AnNS assembled on NiONPs is a good corrosion inhibitor for mild steel in 2 N HCl compared with o-AnNS.