2025/08/29 by Al-Amiery, Ahmed, Shaker, Lina
paper · doi:10.48317/imist.prsm/morjchem-v13i4.57424
This study investigated the application of 6-bromo-2-imino-2H-chromene-3-carboxamide (BIHCC) as a corrosion inhibitor of mild steel in a 1 M HCl solution. The inhibition efficiency and adsorption behavior of the compound were studied by means of potentiodynamic polarization, weight loss measurements and density functional theory (DFT) calculations. In experimental conditions, it demonstrates that the best concentration at which BIHCC could achieve a high level of inhibition efficiency of 81.3% was at an optimum level of 0.5 mM. This is due to the formation of protecting film on mild steel surface, thus reducing the corrosion rate. The inhibition efficiency and corrosion resistance increased with increasing BIHCC concentration, indicating that it is very effective at higher concentrations. Temperature effects were also assessed in measure using the weight loss method and found that immediately there was a minor increase of the inhibition efficiency with the increment in temperature meaning that thermal stability was achieved for the adsorbed BIHCC layer. BIHCC adsorption on mild steel gave satisfaction on the Langmuir model of adsorption isotherm. DFT calculations of electronic indices, namely ΔEgap and EHOMO, further established the strong adsorption potential of the inhibitor and its better performance compared to experimental derived values of adsorption free energy (ΔGads). The agreement of experimental results to the theoretical ones confirms the suitability of BIHCC as an effective corrosion inhibitor and a stable alternative for mild steel in acidic environments.