Insight into the anti-corrosion mechanism Veratrum root extract as a green corrosion inhibitor

[Display omitted] •Electrochemical test data manifested Veratrum root extract (VRE) belong to the mixed-type inhibitor.•Surface characteristics analysis manifested that VRE exhibit excellent anti-corrosion nature.•VRE adsorb on the copper/solution surface in accordance with the Langmuir model. The anticorrosive effect of Veratrum root extract (VRE) as the inhibitor for copper corrosion in H2SO4 solution was studied by electrochemical experiments and quantum chemistry calculation. The electrochemical experiments manifested that VRE exhibited good anticorrosion performance at a range of tested temperatures, which was further manifested by surface characterizations. The results of the Tafel test indicate that VRE belong to mixed corrosion inhibitors, which can simultaneously control the cathodic and anodic reactions of the Cu electrode. When the concentration of VRE is 200 ppm, its anti-corrosion efficiency can reach 97%. Quantum chemical calculation was employed to manifest the mechanism of adsorption and the relationship between the electronic structure of inhibitors and their anticorrosion performance.