Electrokinetics
The electrokinetics is the study of the electric power generation through moving dielectric and the electric fields caused by movement of non-conductors.
Electrokinetic phenomena occur at the interface between two phases when a double layer forms here. As a result of space charges occurring , external electric fields lead to the movement of the fluids involved.
Electrokinetic phenomena are for example:
- Electrophoresis , the migration of electrically charged particles through a substance serving as a carrier material in an electric field
- Electroosmosis , movement of a liquid parallel to a surface through an electric field
- The reverse of electroosmosis: generation of electricity when flowing over a surface
- Generation of an electrical current through moving particles in a liquid, for example during sedimentation .
- Electrocapillarity , the surface tension of a liquid changes when it is electrically charged
Since the electrokinetic phenomena start only at the interface, they can be observed above all in fine-pored material, in capillaries , in suspensions , colloids and other combinations with finely divided bodies and large surfaces.
When salt water runs over an iron plate with a microscopic layer of rust , an electrical charge separation is created. Positively charged ions in salt water attract the negatively charged electrons in iron beneath the thin oxide layer. With the movement of the salt water, the electrons in the iron are pulled along, which represents a generator in the form of a flow cell.
Individual evidence
- ↑ Researched, discovered, developed - news from science. In: Current Research . Deutschlandfunk , July 31, 2019, accessed on August 6, 2019 .
- ^ Franz M. Geiger, Thomas F. Miller, Catherine E. Walker, Paul E. Ohno, Jeongmin Kim: Energy conversion via metal nanolayers . In: Proceedings of the National Academy of Sciences . July 29, 2019, ISSN 0027-8424 , p. 201906601 , doi : 10.1073 / pnas.1906601116 , PMID 31358629 ( pnas.org [accessed August 6, 2019]).