Self-assembled alkanethiol monolayers on a Zn substrate: structure and organization.

This work concerns a first step toward the use of self-assembled monolayers derived from thiols as coupling layers between a zinc surface and organic coatings. The adsorption, structure, and aging of alkanelthiol monolayers on zinc substrates have been studied by contact angle measurements, infrared spectroscopy, and electrochemistry. The thiols self-assemble on the zinc surface to form a highly hydrophobic monolayer. The molecules are well organized with very few gauche defects, oriented nearly normal to the surface, and protect the zinc from oxidation in a neutral aqueous medium.