Study on the microscopic mechanism of ginkgo flavone inhibiting metal corrosion

With the pursuit of sustainable development strategies, the exploration and development of new green corrosion inhibitors that are both efficient and environmentally friendly have become a research focus. Natural product corrosion inhibitors are increasingly favored by corrosion inhibition research due to their wide source of raw materials and biodegradable properties. The flavonoid molecules in Ginkgo biloba fruit have a broad prospect for corrosion inhibition research due to their special skeletal structure. In this work, six major flavonoid molecules were screened and combined with quantum chemistry and molecular dynamics simulations to study their structural features, mechanisms of action, and adsorption processes on metal surfaces. The quantum chemical results showed that the frontline molecular orbitals were concentrated on the flavonoid skeleton, and ginkgolides, quercetin, and ginkgo biflavonoids had larger adsorption capacities on metals. The Fukui index calculations showed that the carbonyl oxygen atom and the hydroxyl oxygen atom were the main nucleophilic and electrophilic attack sites. The molecular dynamics simulation showed that the corrosion inhibitor-metal interface model converged to the equilibrium state after 500 ps, and the adsorption mode of each molecule on the iron surface was mainly parallel adsorption, which provided a reliable theoretical basis for the interpretation of the corrosion inhibition mechanism of such molecules.