Dispersion (materials science)
Encyclopedia
In materials science
, dispersion is the fraction of atoms of a material exposed to the surface. In general:
where D is the dispersion, NS is the number of surface atoms and NT is the total number of atoms of the material. Dispersion is an important concept in heterogeneous catalysis
, since only atoms that are exposed to the surface are able to play a role in catalytic surface reactions. Dispersion increases with decreasing crystallite size and approaches unity at a crystallite diameter of about 1 nm.
Materials science
Materials science is an interdisciplinary field applying the properties of matter to various areas of science and engineering. This scientific field investigates the relationship between the structure of materials at atomic or molecular scales and their macroscopic properties. It incorporates...
, dispersion is the fraction of atoms of a material exposed to the surface. In general:
- D = NS/NT
where D is the dispersion, NS is the number of surface atoms and NT is the total number of atoms of the material. Dispersion is an important concept in heterogeneous catalysis
Catalysis
Catalysis is the change in rate of a chemical reaction due to the participation of a substance called a catalyst. Unlike other reagents that participate in the chemical reaction, a catalyst is not consumed by the reaction itself. A catalyst may participate in multiple chemical transformations....
, since only atoms that are exposed to the surface are able to play a role in catalytic surface reactions. Dispersion increases with decreasing crystallite size and approaches unity at a crystallite diameter of about 1 nm.