Enhanced corrosion inhibition performance of 5-amino-3‑bromo-1-methylindazole on copper in sulfuric acid environments

The corrosion inhibitor 5-amino-3‑bromo-1-methylindazole (ABMI) with multiple substituents can effectively protect the copper substrate. According to the electrochemical experiment results, at 298 K, 3 mM ABMI may suppress copper corrosion by 92.1 %. Furthermore, going from 298 K to 308 K raises the temperature at which 3 mM ABMI may continue to suppress corrosion with an efficiency exceeding 90 %. The weight loss test, SEM, AFM, and XRD data all reveal that the presence of ABMI efficiently prevents the corrosion media from dissolving the copper substrate. The $\Delta G_{ads}^0$ value of ABMI is −32.97 kJ/mol, demonstrating that it works on the metal/solution interface through physical adsorption and chemisorption. The results of molecular dynamics modeling and quantum chemical computation show that ABMI adsorbs to the metal superficies in a nearly parallel way, minimizing the exposure area among the metal superficies with the medium with corrosive substances and providing the best possible protection for copper.