Adsorbed Layers
The study of adsorption and adsorbed layers is one of the most fundamental issues in surface chemistry. It forms the foundation for the understanding of surface modification as well as colloid stability.
Information given includes the dynamics of adsorption, competitive adsorption as well as behavior of surface layers being subjected to various disturbances.
Ellipsometry and Reflectometry
In ellipsometry and reflectometry the surface is illuminated with elliptically polarized light. Upon reflection at the surface the polarization is perturbed. If the surface contains adsorbed molecules this perturbation is different and depends on the amount of adsorbed molecules. Ellipsometry gives information on the adsorbed amount as well as the dynamics of adsorption.
Dual polarization interferometer
This instrument makes use of the fact that light traveling in a solid picks up information from the surface giving a phase shift of the light. Thus, when comparing with the phase of the original light one detects adsorption of molecules at the surface. The method allows the determination of the adsorption dynamics.
Quartz crystal microbalance, QCM
In the QCM technique a quartz crystal is made to oscillate at its resonance frequency. As this resonance frequency is highly dependent on the mass of the crystal it can be used to determine adsorption at its surface. An advantage of the method is that it can be used in turbid solutions.