Utilization of pyrazole-perimidine hybrids bearing different substituents as corrosion inhibitors for 304 stainless steel in acidic media


Ugus O., GÜMÜŞ M., SERT Y., KOCA İ., KOCA A.

JOURNAL OF MOLECULAR STRUCTURE, vol.1262, 2022 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 1262
  • Publication Date: 2022
  • Doi Number: 10.1016/j.molstruc.2022.133025
  • Title of Journal : JOURNAL OF MOLECULAR STRUCTURE
  • Keywords: Pyrazole-perimidine hybrids, Corrosion inhibition, Potentiodynamic polarization, Electrochemical impedance spectroscopy, DFT, MILD-STEEL CORROSION, CARBON-STEEL, PYRIMIDINE-DERIVATIVES, ORGANIC-COMPOUNDS, GREEN, RESISTANCE, HCL, ELECTRONEGATIVITY, ALUMINUM, BROMIDE

Abstract

Water soluble Pyrazole-Perimidine (PYR-PER) hybrids bearing various anchoring groups has been synthesized and their corrosion inhibitive efficiencies for the 304 stainless steel in 1.0 M hydrochloric acid has been investigated by the electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PDP), open circuit potential (OCP) measurements, and Density Functional Theory (DFT) B3LYP functional combined with 6-311 ++ G(d,p) basis set. The analyses show that all PYR-PER hybrids effectively reduced the corrosion current density, increased corrosion resistance and inhibited the corrosion of the 304 stainless steel in 1.0 M hydrochloric acid at 298 K. The results indicated that the hybrids functioned as a mixed type inhibitors with anodic suppression outweighing the cathodic one. Multi-functional heteroatoms and methyl, fluoride, chloride, and bromide substituents of pyrazole derivatives considerably enhanced the inhibition efficiencies of the hybrids. The highest corrosion inhibitive efficiency (as 97.45%) was achieved with PYR-PER3 bearing methyl and bromide anchoring groups on the benzene group of the main PYR-PER structure. Some quantum chemical parameters, EHOMO, ELUMO, AE , electronegativity, chemical hardness, chemical softness, electrophilicity index, proton affinity and AN electron transfer were also discussed. Additionally non-linear optical properties (NLO) were investigated. The results in the B3LYP technique supported by experimental results. (C)& nbsp;2022 Elsevier B.V. All rights reserved.