Theoretical\nand Experimental Investigation of Indazole\nDerivatives as Corrosion Inhibitors for Copper in Acidic Medium

To\nexplore the slow-release potential of indole oxygen-containing\nfunctional group derivatives in acidic media in order to reduce their\nnegative impact on the environment. We investigated the corrosion\ninhibition effect of 5-Methoxy-indazole (MIA) and Methyl 1H-indazole-5-carboxylate\n(MIC) on copper in H<sub>2</sub>SO<sub>4</sub> through electrochemical\ntesting, X-ray photoelectron spectroscopy (XPS), scanning electron\nmicroscopy (SEM) analysis, and theoretical calculations. Research\nhas found that MIA and MIC exhibit excellent corrosion inhibition\nperformance, with MIA achieving an efficiency of up to 91.04%. SEM\nobserved that MIA and MIC formed a protective film on the copper surface,\neffectively isolating the corrosive medium. The adsorption behavior\nconforms to the Langmuir model, indicating the coexistence of chemical\nand physical adsorption. Density functional theory calculations (DFT)\nand molecular dynamics simulations (MD) further revealed the corrosion\ninhibition mechanism of imidazole derivatives, emphasizing their potential\nfor application in acidic media. These results not only elucidate\nthe corrosion inhibition effect of imidazole compounds, but also provide\nnew ideas for corrosion control in acidic environments.