Corrosion inhibition, surface adsorption and computational studies of Swertia chirata extract: A sustainable and green approach

The aerial parts extracted from Swertia chirata (S. chirata) plant were employed for the corrosion resistance of carbon steel in the acidic medium (0.5 M H2SO4) utilizing by weight-loss method, Tafel and EIS. The state of mixed inhibitor adsorption on the carbon steel surface were shown by potentiodynamic polarization. S. chirata achieved the extraordinary inhibition efficiency of 92.32% at 500 mg/L of inhibitor concentration. SEM and AFM were used to know about the thin layer formed on the surface of carbon steel for its protection from corrosion and the adsorption of inhibitors shown by UV–vis analysis FT-IR technique confirmed the existence of functional groups and the heteroatoms exhibited in the inhibitor. Adsorbance by the inhibitory molecules on the carbon steel surface followed the Langmuir adsorption isotherm. Theoretical investigations (computational) showed a precious report which was supported by experimental results. All acquired outcomes ensure that S. chirata extract can procedure an effectual preventing layer and restrict the corrosion procedure. •S. chirata aerial parts extract was analyzed a green corrosion inhibitor.•The corrosion inhibition efficiency of S. chirata extract is >92% at 500 mg/L.•The adsorption of S. chirata extract was investigated by using SEM and AFM.