Insight into the corrosion inhibition performance of Jasmine flower extract on copper in sulfuric acid medium using experimental and theoretical calculation methods

Background: Copper is widely used in all areas of society, but it is easy to be corroded in corrosive media, which causes certain economic losses. Among many anti-corrosion methods, adding corrosion inhibitors is an efficient, convenient and common method. However, there are some shortcomings in traditional corrosion inhibitors, so it is urgent to develop an efficient corrosion inhibitor with no toxicity and low cost as well as no harm to the environment. Methods: The corrosion performance of Jasmine flower extract (JFE) for copper in 0.5 mol/L sulfuric acid medium was studied by electrochemical test, and the microstructure and chemical composition of copper surface were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM) and atomic force microscope (AFM). The interaction mechanism between corrosion inhibitor molecules and copper was analyzed based on theoretical calculation. Significant findings: The results show that JFE is an efficient and environment-friendly corrosion inhibitor. In a certain temperature range (298 similar to 308 K), when the concentration of JFE is 500 mg/L, the corrosion inhibition efficiency (eta) is not less than 94.0%. According to Langmuir adsorption model, the JFE adsorbs on the copper surface as a mixed type of inhibitor.