Controlled Design and Mechanism of Highly Protective Performance for Copper Surface by Electrolysis Technique

In order to promote the formation of coordination bonds and intermolecular cross-linking, a mercaptopropyltrimethoxysilane (MPTS) film was designed on the copper foil surface by an electrolysis process in this study. The morphology and composition of the MPTS film were characterized. The bonding force between the MPTS film and the copper foil, and its anticorrosion performance, were evaluated. Finally, the formation mechanism of the MPTS film was revealed by theoretical calculations. The results show that the MPTS film prepared by the electrolysis process is uniform and dense. The sulfhydryl groups (-SH) of the MPTS molecule form S-Cu bonds with cuprous ions; meanwhile, the Si-OH groups form a Si-O-Si cross-linking structure. Compared with the traditional immersion method, the bonding force between the MPTS film and copper foil prepared by the electrolysis process is increased by 40%, and the corrosion-protection performance is improved by 10 times. The results of theoretical calculations indicate that the enhanced activity of MPTS ionization hydrolysis leads to easier adsorption on the metal surface. In addition, the application of an anodic potential increases the binding energy of MPTS on the Cu(111) surface. The synergistic promotion of the formation of S-Cu and Si-O-Si bonds is of great significance in enhancing the performance of the MPTS film. In this study, the MPTS film prepared on copper surfaces by the electrolysis process exhibits excellent adhesion and corrosion resistance. It not only holds significant application value in copper corrosion protection but also demonstrates broad prospects in functionalizing inert metal surfaces and the surface treatment of copper water pipelines.