Theoretical and Experimental Investigation of Indazole Derivatives as Corrosion Inhibitors for Copper in Acidic Medium

To explore the slow-release potential of indole oxygen-containing functional group derivatives in acidic media in order to reduce their negative impact on the environment. We investigated the corrosion inhibition effect of 5-Methoxy-indazole (MIA) and Methyl 1H-indazole-5-carboxylate (MIC) on copper in H₂SO₄ through electrochemical testing, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) analysis, and theoretical calculations. Research has found that MIA and MIC exhibit excellent corrosion inhibition performance, with MIA achieving an efficiency of up to 91.04%. SEM observed that MIA and MIC formed a protective film on the copper surface, effectively isolating the corrosive medium. The adsorption behavior conforms to the Langmuir model, indicating the coexistence of chemical and physical adsorption. Density functional theory calculations (DFT) and molecular dynamics simulations (MD) further revealed the corrosion inhibition mechanism of imidazole derivatives, emphasizing their potential for application in acidic media. These results not only elucidate the corrosion inhibition effect of imidazole compounds, but also provide new ideas for corrosion control in acidic environments.