The inhibition mechanism and adsorption behavior of three purine derivatives on the corrosion of copper in alkaline artificial seawater: Structure and performance

Abstract

The inhibition mechanism and adsorption behavior of three purine derivatives (guanine (G), adenine (A), and hypoxanthine (I)) on the corrosion of copper in alkaline artificial seawater were studied by electrochemical tests, scanning electron microscopy (SEM), X-ray spectroscopy (XPS), quantum chemical calculation and molecular dynamics simulation. The results showed that the three inhibitors all delayed corrosion by indicating a protective film on the copper surface, and the order of their inhibition efficiency was I > G > A. The three inhibitors all obeyed the Langmuir adsorption model and belonged to a mixed physical and chemical adsorption. The G and I molecules were adsorbed on the copper surface in parallel, covering the copper surface to the greatest extent, thus playing a better inhibition effect. And the A was arranged obliquely at a certain angle with the copper surface, so its inhibition effect was relatively low. This research could help us explore the influence of functional groups on its inhibition performance and make improvements.