Surface science

The science encompasses concepts such as heterogeneous catalysis, semiconductor device fabrication, fuel cells, self-assembled monolayers, and adhesives.

Gerhard Ertl in 1974 described for the first time the adsorption of hydrogen on a palladium surface using a novel technique called LEED.

Instead, well-defined single crystal surfaces of catalytically active materials such as platinum are often used as model catalysts.

[9] Relationships between the composition, structure, and chemical behavior of these surfaces are studied using ultra-high vacuum techniques, including adsorption and temperature-programmed desorption of molecules, scanning tunneling microscopy, low energy electron diffraction, and Auger electron spectroscopy.

[12][13] These studies link traditional electrochemical techniques such as cyclic voltammetry to direct observations of interfacial processes.

Many of these techniques require vacuum as they rely on the detection of electrons or ions emitted from the surface under study.

This is found by an order of magnitude estimate for the (number) specific surface area of materials and the impingement rate formula from the kinetic theory of gases.

Acoustic techniques, such as quartz crystal microbalance with dissipation monitoring, is used for time-resolved measurements of solid–vacuum, solid–gas and solid–liquid interfaces.

While some of these measurements can be performed using laboratory X-ray sources, many require the high intensity and energy tunability of synchrotron radiation.

Grazing-incidence small angle X-ray scattering (GISAXS) yields the size, shape, and orientation of nanoparticles on surfaces.

[19] The crystal structure and texture of thin films can be investigated using grazing-incidence X-ray diffraction (GIXD, GIXRD).

Surface sensitivity is achieved by detecting photoelectrons with kinetic energies of about 10–1000 eV, which have corresponding inelastic mean free paths of only a few nanometers.

For example, they make it possible to follow reactions at the solid–gas interface in real space, if those proceed on a time scale accessible by the instrument.