Inhibition Potentials of Solanum macrocarpon Leave Extract as a Green Corrosion Inhibitor of Mild Steel in an Acidic Solution

Green organic inhibitors have become a more efficient alternative to inorganic inhibitors in mild steel (MS) corrosion in industries due to their cheap and eco-friendly characteristics. Gasometric techniques were used to investigate the adsorption and inhibitive qualities of a methyl alcohol extract of Solanum macrocarpon (SM) leaves as a green inhibitor for the corrosion of MS in 2-M sulfuric acid solutions, respectively, at 303–323 K. Fourier Transform Infrared (FTIR) and qualitative phytochemical analysis were done to elucidate the functional group and organic compounds present in the leaf extract. The inhibition efficiency (IE) increased with concentration and decreased with temperature. The results showed that at a temperature of 303 K, 91.4% IE was reached at 0.5% w/v extract concentration, and thus indicating that methanol extract of Solanum macrocarpon leaves is suitable for corrosion inhibition. Furthermore, the inhibitory potential of the plant extract was ascertained due to the existence of organic compounds containing heteroatoms in their functional groups. The corrosion mechanism was shown to be physical adsorption using thermodynamics parameters ( \({E}_{\text{a}}\) $E_{\text{a}}$ and \(\Delta {G}_{\text{ads}}\) $\mathrm{\Delta }{G}_{\text{ads}}$ ). According to the findings, SM methanol extract has the potential to be an affordable corrosion inhibitor for industrial use.