Dispersion (surface chemistry)
The dispersion D in surface chemistry is defined as
with : number of atoms on the surface and : total number (bulk) of atoms in the solid / nanoparticle / cluster
The dispersion is the ratio of surface atoms to total atoms of a solid or nanoparticle. With the closest packing of atoms, the dispersion decreases with the number of atoms.
example
For a cluster that consists of four tetrahedrally arranged spherical atoms, for example, D = 100%, because here each atom is a surface atom.
Dispersion when adsorbed on surfaces
In adsorption processes , the dispersion of surfaces depends on the strength of the interaction of the adsorbate with the surface.
- Low dispersion occurs when the interactions between the adsorbed particles are stronger than with the surface.
- High dispersion occurs when the adsorbed particles interact more strongly with the surface than with their peers.