Formation of Ordered Self-Assembled Monolayers by Organic Thioacetates and Thiocyanates on Au(111)

Abstract

Self-assembled monolayers (SAMs), formed by the spontaneous adsorption of organosulfur compounds on gold, offer an excellent means to control the physical and chemical properties of surfaces for various technological applications in biosensing, nanopatterning, corrosion inhibition, and molecular electronic devices [1-3]. In particular, alkanethiol SAMs on gold have been frequently used in the field of various practical applications. However, one of drawbacks for construction of organosulfur SAMs is that the thiol group can be oxidized to disulfides and/or other oxidized compounds during SAM formation in solution. In order to overcome this problem, the SAMs prepared by organic thioacetate and thiosulfates having a high chemical stability for oxidation were fabricated and characterized by various surface sensitive techniques, especially, scanning tunneling microscopy. In this talk, we will provide new molecular features of these SAMs on Au(111) and information on how to control two-dimensional (2D) ordered phases of SAMs. The 2D ordered structure of these SAMs can be obtaining by adjusting solution temperature, solvent properties, and deposition methods.