Electric surface charge

Electric surface charge appears practically always on an object surface when it is placed into a fluid. All fluids contain ions, positive (cations) and negative (anions). These ions interact with the object surface. This interaction might lead to adsorption some of them on the surface. If number of adsorbed cations exceeds number of adsorbed anions, surface would gain total positive electric charge.

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There is another possible mechanism leading to surface charging. It is dissociation of the surface chemical group.

Details of the electric surfface charge description and its relation to the surface chemistry are given by Lyklema in "Fundamentals of Interface and Colloid Science" ^[1]

References

1. ^ Lyklema, J. “Fundamentals of Interface and Colloid Science”, vol.2, page.3.208, 1995

Category

Interface and Colloid Science