Assessment of ethanolic extract of Dittrichia viscosa from Kardoussa Douar region of Taza in Morocco as antioxidant and green inhibitor for carbon steel corrosion in acidic medium

This study targeted evaluating the anticorrosive and antioxidative characteristics of Dittrichia viscosa ( ZS-OH ) extract. ZS-OH was first extracted by deploying a soxhlet and characterized by chromatographic analysis (GC/MS). In addition, a quantitative assessment of the total phenolic (TPC) and flavonoids (FC) content of the ZS-OH extract, as well as phytochemical analyses, were carried out. Antioxidant testing was conducted using the bioassay: 2,2-diphenyl-1-picrylhydrazyl (DPPH). The ability of ZS-OH extract to stymie the corrosion of carbon steel in 1.0 M HCl was considered through potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). ZS-OH extract yield was 4.73 %, and GC-MS revealed 32 distinct chemicals. Neryl isovalerate (29.8 %), 1,10-di-epi-Cubenol (25.4 %), and 2,5-dimethoxy-p-cymene (11.6 %) made up the majority of the ZS-OH extract. The electrochemical results reveal that the ZS-OH extract acts as a mixed-type with an inhibition efficiency of up to 96.8 % at 500 ppm under 303 K. Surface analyses using SEM/EDS confirmed the formation of the protective layer of ZS-OH extract molecules on the C-S surface. The three major components are fully optimized in the DFT through the B3LYP functional and 6–311++G(d,p) basis sets. Molecular dynamics simulation data show the molecules of ZS-OH extract oriented beneficially on metal surfaces, providing a high surface coverage, and thus, a high inhibition performance.