Benzothiazole derivatives-based supramolecular assemblies as efficient corrosion inhibitors for copper in artificial seawater: Formation, interfacial release and protective mechanisms

Host-guest assemblies for beta-cyclodextrin (beta-CD) loaded with 2-mercaptobenzothiazole (MBT) or 2-aminobenzothiazole (ABT) were constructed to distinguish their anticorrosive mechanisms for copper in aqueous phase. Their protective efficacies were assessed by weight-loss, electrochemical, surface and solution analyses for copper in the artificial seawater. Achievements proposed that MBT and ABT were stably incorporated in beta-CD with distinct thermodynamic traits, which earned the optimal inhibition efficiencies of 95.6 % and 89.2 % at 0.5 g/L dosage following cathodic-dominated mixed-type inhibition mechanism. Coupling theoretical simulations, varied guest release mechanisms and different bonding strengths of Cu-S and Cu-N accounted for the differentiated inhibition behaviors.

Automated summary

Host-guest assemblies of beta-cyclodextrin (beta-CD) loaded with 2-mercaptobenzothiazole (MBT) or 2-aminobenzothiazole (ABT) were used to distinguish their anticorrosive mechanisms for copper in aqueous phase. The protective efficacies were evaluated and MBT and ABT showed optimal inhibition efficiencies of 95.6% and 89.2% respectively using cathodic-dominated mixed-type inhibition mechanism at a dosage of 0.5 g/L. The differentiated inhibition behaviors were attributed to varied guest release mechanisms and different bonding strengths of Cu-S and Cu-N, as supported by theoretical simulations.