Electrochemical and theoretical investigation of three novel quinazoline derivatives as corrosion inhibitors for mild steel in 1.0 M HCl acidic medium

초록

New quinazoline derivatives, Q-Cl, Q-N(CH3)2, and Q-NO2, were synthesised and characterised by FT-IR. Their corrosion inhibition on mild steel in 1.0 M HCl at 298 was studied using electrochemical methods, SEM-EDX, DFT, and Monte Carlo simulations. All molecules showed excellent inhibition efficiencies of 99.38%, 99.91% and 91.65% for Q-Cl, Q-N(CH3)2, and Q-NO2, respectively. Corrosion current densities decreased to 6 mu A<middle dot>cm-2 for Q-Cl, 50 mu A<middle dot>cm-2 for Q-N(CH3)2, and 82 mu A<middle dot>cm-2 for Q-NO2, confirming reduced corrosion rates. Increasing temperature (298-338 K) decreased efficiency. Activation and thermodynamic parameters indicated chemical adsorption dominated by chemisorption, confirmed by Langmuir's isotherm. The novelty lies in the synthesis of new quinazoline derivatives tested for the first time as corrosion inhibitors in 1.0 M HCl. Their donor and acceptor substituents near aromatic rings enhance electron density and strengthen steel interactions, achieving remarkable inhibition even at low concentrations. This study offers valuable insights into developing efficient structure-based corrosion inhibitors. On a synth & eacute;tis & eacute; et caract & eacute;ris & eacute; par FT-IR de nouveaux d & eacute;riv & eacute;s de la quinazolone, Q-Cl, Q-N(CH3)2 et Q-NO2. On a & eacute;tudi & eacute; leur inhibition de la corrosion sur l'acier doux dans le HCl 1.0 M & agrave; 298 K en utilisant des m & eacute;thodes & eacute;lectrochimiques, MEB-EDX, DFT et des simulations de Monte Carlo. Toutes les mol & eacute;cules ont montr & eacute; d'excellentes efficacit & eacute;s d'inhibition de 99.38%, 99.91% et 91.65% pour Q-Cl, Q-N(CH3)2 et Q-NO2, respectivement. Les densit & eacute;s du courant de corrosion ont diminu & eacute; & agrave; 6 mu A cm-2 pour Q-Cl, 50 mu A cm-2 pour Q-N(CH3)2 et 82 mu A cm-2 pour Q-NO2, confirmant la r & eacute;duction des taux de corrosion. L'augmentation de la temp & eacute;rature (de 298 & agrave; 338 K) a diminu & eacute; l'efficacit & eacute;. Les param & egrave;tres thermodynamiques et d'activation ont indiqu & eacute; une adsorption chimique domin & eacute;e par la chimisorption, confirm & eacute;e par l'isotherme de Langmuir. La nouveaut & eacute; r & eacute;side dans la synth & egrave;se de nouveaux d & eacute;riv & eacute;s de quinazolone & eacute;valu & eacute;s pour la premi & egrave;re fois comme inhibiteurs de corrosion dans le HCl 1.0 M. Leurs substituants donneurs et accepteurs & agrave; proximit & eacute; des cycles aromatiques am & eacute;liorent la densit & eacute; & eacute;lectronique et renforcent les interactions avec l'acier, atteignant une inhibition remarquable m & ecirc;me & agrave; de faibles concentrations. Cette & eacute;tude offre des informations pr & eacute;cieuses pour le d & eacute;veloppement d'inhibiteurs de corrosion efficaces bas & eacute;s sur la structure.

키워드