Electrokinetic phenomena are a family of several different effects that occur in
heterogeneousfluids, or in porous bodies filled with fluid, or in a fast flow over a flat surface. The term
heterogeneous here means a fluid containing particles. Particles can be
solid, liquid or
gas bubbles with sizes on the scale of a
micrometer or
nanometer.[1][2][3] There is a common source of all these effects—the so-called
interfacial 'double layer' of charges. Influence of an external
force on the
diffuse layer generates tangential motion of a fluid with respect to an adjacent charged surface. This force might be
electric,
pressure gradient,
concentration gradient, or
gravity. In addition, the moving phase might be either continuous
fluid or
dispersed phase.
Family
Various combinations of the driving force and moving phase determine various electrokinetic effects. According to J.Lyklema, the complete family of electrokinetic phenomena includes:[4]
electrophoresis, as motion of charged particles under influence of electric field;
electro-osmosis, as motion of liquid in porous body under influence of electric field;
^ International Standard ISO 13099-1, 2012, "Colloidal systems – Methods for Zeta potential determination- Part 1: Electroacoustic and Electrokinetic phenomena"
^Hunter, Robert (2001). Foundations of colloid science. Oxford: Oxford University Press.
ISBN9780198505020.
^
abDukhin, A. S. and Goetz, P. J. Characterization of liquids, nano- and micro- particulates and porous bodies using Ultrasound, Elsevier, 2017
ISBN978-0-444-63908-0
^
abLyklema, J. (1995) Fundamentals of Interface and Colloid Science, Vol. 2, p. 3.208.
^Hunter, R.J. (1989) Foundations of Colloid Science, Oxford University Press.
^Dukhin, S.S. and Derjaguin, B.V. (1974) Electrokinetic Phenomena, J. Willey and Sons.
^Russel, W.B., Saville, D.A., and Schowalter, W.R. (1989) Colloidal Dispersions, Cambridge University Press.