Surface Coordination and Polymerization of Allyl Mercaptan Passivates the Oxidation of Copper

The oxidation of copper significantly restricts its widespread industrial applications. Traditional methods, such as alloying and anti-corrosion coatings, often compromise copper's electrical and thermal conductivity. Molecular passivation technology has emerged as a promising solution, enhancing copper's anti-corrosion properties without degrading its intrinsic physical characteristics. However, the enhancement of copper's anti-corrosion properties through molecular passivation is far from satisfactory. Herein, allyl mercaptan is employed as a molecular passivation monomer to investigate its anti-corrosion performance. It is demonstrated that allyl mercaptan can coordinate and polymerize on copper surfaces under mild conditions, forming polymeric passivation layers. The modified copper foil (Cu-AM) exhibits a corrosion-inhibiting efficiency of 99.65%. Density functional theory (DFT) calculations indicate that the coordination of allyl mercaptan on various copper crystal planes is spontaneous, with the dissociation adsorption energy ranking as Cu(100) > Cu(110) > Cu(111). Anti-corrosion experiments on single-crystal copper foils further corroborate these findings, showing that Cu(100)-AM achieves the highest corrosion-inhibiting efficiency of 99.91%.