Kinetics of Adsorption and Desorption of Non-Covalent Self-Assembling Systems

Abstract

Self-Assembling systems that rely on non-covalent forces to drive ordering are the subject of intense study. Of particular interest are redox active systems like porphyrins and phthalocyanines that can generate self-assembled monolayers (SAMs) at the solution-solid interface. These offer the potential of creating highly ordered films from the simple process of solution dipping. In recent years, it has become clear that kinetics plays a significant role in determining the structure of these films. However, very little is known about the rates and mechanisms of the formation and stability of these interesting surface layers. In this talk we will present new data and models for the adsorption and desorption kinetics of non-covalent SAMs on gold surfaces. As might be suspected, the adsorption and desorption rates do not follow simple Langmuir behavior. Also, the potential for multilayer growth must be considered.