LAUSR

Abstract Conventional organic and inorganic corrosion inhibitors are noxious and hazardous to living organisms and the environment. Therefore, the use of plant extracts as potential corrosion inhibitors for metals has attracted considerable attention because these compounds are renewable and can have low toxicity, mainly when derived from edible plant species. Here, we prepared Atriplex leucoclada extract (ALE, 0–8 g/L) and tested its effectiveness as an eco-friendly copper corrosion inhibitor in 1 M HCl using several characterisation techniques, such as potentiodynamic polarisation experiments at the open-circuit potential, electrochemical impedance spectroscopy, and surface morphology. Adsorption isotherm modelling based on the Langmuir monolayer adsorption model revealed that the antioxidant flavonoids and polyphenolic compounds in ALE adsorb on the surface of copper and act as mixed-type inhibitors to reduce copper corrosion. Notably, the use of ALE resulted in a high (91.5%) inhibition efficiency at room temperature. Our results demonstrate the potential of ALE as a corrosion inhibitor for copper in acidic media and enrich knowledge regarding the use of plant extracts as green corrosion inhibitors.