The enhancement and mechanism of potential-assisted method on 2-mer-captobenzobthiazole assembled film for copper protection

Self-assembled organothiol is a well-known process to endow specific protective properties and usually involves passive incubation. Researchers have recently confirmed that the potential-assisted method is more selective and faster than the passive method. This paper provides an original and promising approach for Cu protection by 2mercaptobenzobthiazole (MBT) assembled film prepared from an aqueous solution within minutes under potential control. Electrochemical studies, salt spray tests, and XPS highlight and confirm the benefits of this method to result in film features, organic solvent-free, and considerable savings of preparation time. Experimental results also demonstrate that the substrate potential exerts a significant effect on the quality of MBT film. The effectiveness of negative potential in MBT film formation can be attributed to two aspects: first, it can inhibit the oxidation of Cu metal to Cu(II) in the aqueous solution, and second, it can make MBT molecule bond to Cu mainly through forming thiolate Cu-S bond with its exocyclic S atom.