Term: superequivalent adsorption
https://doi.org/10.1351/goldbook.S06140

Definition:
This occurs when the specifically adsorbed amount of charge in the inner Helmholtz plane is higher than the charge on the metal phase, taken with the reverse sign.

Related Terms:
1) inner helmholtz plane (http://doi.org/10.1351/goldbook.I03048).

Source: PAC, 1986, 58, 437. 'Interphases in systems of conducting phases (Recommendations 1985)' on page 448 (https://doi.org/10.1351/pac198658030437)

Citation: 'superequivalent adsorption' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.S06140

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