Michael J. Hostetler

Colloids and self-assembled monolayers

The fusion of disparate areas of study can produce results that give insight both into the original topics and into new subjects. Such has been the case for the areas of colloids and self-assembled monolayers (SAMs). For example, an alkanethiolate monolayer bound to the surface of a gold colloid prevents aggregation of the metal particles, stabilizes them to harsh reaction conditions, and enhances their solubility in many organic solvents. The monolayer on the colloid (referred to as a 3D-SAM) can be studied by powerful techniques unavailable to conventional 2D-SAMs, including differential scanning calorimetry, NMR spectroscopy, and transmission infrared spectroscopy. Finally, other areas, such as the behavior of nanoelectrodes, the production of improved substrates for surface-enhanced Raman spectroscopy, and the advent of scanning tunneling microscopy (STM) measurements on the electronic properties of single clusters and molecules, have directly benefited from the interaction of colloids and SAMs.