Title: diffusion layer
Long Title: IUPAC Gold Book - diffusion layer
DOI: 10.1351/goldbook.D01725
Status: current

Definition
The region in the vicinity of an electrode where the concentrations are different from their value in the bulk solution. The definition of the thickness of the diffusion layer is arbitrary because the concentration approaches asymptotically the value \(c_{0}\) in the bulk solution (see diagram). 

Related Terms
- Nernst's diffusion layer: https://goldbook.iupac.org//terms/view/N04108
- diffusion: https://goldbook.iupac.org//terms/view/D01716

Source
- PAC, 1981, 53, 1827. 'Nomenclature for transport phenomena in electrolytic systems' on page 1837 (https://doi.org/10.1351/pac198153101827)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/D01725/html
- json: https://goldbook.iupac.org/terms/view/D01725/json
- xml: https://goldbook.iupac.org/terms/view/D01725/xml

Citation: Citation: 'diffusion layer' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.D01725
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Accessed: 2026-05-11T20:09:53+00:00