Term: diffusion layer thickness
https://doi.org/10.1351/goldbook.D01726

Definition:
Defined by the equation: \[\delta = \frac{D}{k_{\text{d}}}=\frac{n\ F\ D\ c\ A}{l_{i}}\] where D is the diffusion coefficient, kd is the heterogeneous diffusion rate constant, F is the Faraday constant, c is the concentration, A is the geometric area of the electrode, li is the limiting current and n is the charge number of the cell reaction.

Related Terms:
1) diffusion coefficient (http://doi.org/10.1351/goldbook.D01719).
2) faraday constant (<em>in electrochemistry</em>) (http://doi.org/10.1351/goldbook.F02325).
3) heterogeneous diffusion rate constant (<em>in electrochemistry</em>) (http://doi.org/10.1351/goldbook.H02805).
4) limiting current (<em>in electrochemistry</em>) (http://doi.org/10.1351/goldbook.L03532).
5) charge number of the cell reaction (<em>in electrochemistry</em>) (<em>of a cell reaction</em>) (http://doi.org/10.1351/goldbook.C00995).

Source: PAC, 1974, 37, 499. 'Electrochemical nomenclature' on page 513 (https://doi.org/10.1351/pac197437040499)

Citation: 'diffusion layer thickness' 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.D01726

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