Novel saccharin derivatives are inhibitors for carbon steel corrosion in 1 M HCl: electrochemical, thermodynamic and theoretical assessment

In this study, computational and experimental approaches were used to assess the anti-corrosive performance of two new saccharin derivatives, N-benzoyl saccharin (NBS) and N-allyl saccharin (NAS), for carbon steel corrosion in 1 M HCl.The electrochemical outcomes (potentiodynamic polarization (PDP)/electrochemical impedance spectroscopy (EIS)) revealed that NAS had a higher protection efficiency with an icorr value of 85.07 (μA/cm 2 ) and a charge transfer resistance (Rct) value of 200.43 (Ω•cm 2 ) than NBS, which had an icorr value of 108.59 (μA/cm 2 ) and an Rct value of 149.8 (Ω•cm 2 ).Furthermore, our inhibitors demonstrated strong inhibitory effects in the reduction of hydrogen evolution, and the inhibition efficiency at 1 mM followed the order: NAS ((PDP (90.27%) and EIS (90.60%))>NBS ((PDP (87.58%) and EIS (87.42%)).Furthermore, surface morphology studies (SEM/EDX) definitely verified the formation of protective layers as a result of the adsorption of the investigated inhibitors onto the metal surface.DFT (Density functional theory) study demonstrated that NBS and NAS interact with the metallic surface via donor-acceptor interactions, with electron-rich centers acting as the most favorable locations for the interactions.The adsorption of the NBS and NAS molecules on the metal surface is demonstrated using MC (Monte Carlo), and MD (Molecular dynamic) simulations.Different experimental and computational research agree well.