Abstract
AbstractCathodic protection was introduced two centuries ago and since has found widespread application in protecting structures such as pipelines, offshore installations, and bridges from corrosion. Despite its extensive use, the fundamental working mechanism of cathodic protection remains debated, particularly for metals in porous media such as soil. Here, we use in-situ and ex-situ characterisation techniques coupled with electrochemical measurements to characterise the spatio-temporal changes occurring at the steel-electrolyte interface. We show that upon cathodic protection, the interfacial electrolyte undergoes alkalinisation and deoxygenation, and that depending on polarisation conditions, an iron oxide film can simultaneously form on the steel surface. We further demonstrate that these changes in interfacial electrolyte chemistry and steel surface state result in altered anodic and cathodic reactions and their kinetics. We propose a mechanism of cathodic protection that integrates previous theories, based on both concentration and activation polarisation, complimentarily. We discuss the implications of this study in enhancing corrosion protection technologies and the safe, economical, and environmentally friendly operation of critical steel-based infrastructures.
Publisher
Springer Science and Business Media LLC
Reference70 articles.
1. Davy, H. On the corrosion of copper sheeting by sea water, and on methods of preventing this effect; and on their application to ships of war and other ships. Philos. Trans. R. Soc. Lond. B Biol. Sci. 114, 151–158 (1824).
2. James, F. A. Davy in the dockyard: Humphry Davy, the Royal Society and the electrochemical protection of the copper sheeting of his majesty’s ship in the mid 1820s. Phys. 19, 205–225 (1992).
3. Ruston, S. Humphry Davy: analogy priority and the “true philosopher. Ambix 66, 121–139 (2019).
4. Carré, C. et al. Electrochemical calcareous deposition in seawater. A review. Environ. Chem. Lett. 18, 1193–1208 (2020).
5. Hartt, W. H., Culberson, C. H. & Smith, S. W. Calcareous deposits on metal surfaces in seawater—a critical review. Corrosion 40, 609–618 (1984).
Cited by
4 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献