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292:, dissociation of a ligand, or a change in geometry. Deviations from linearity can be expected at very short time scales due to non-ideality in the potential step. At long time scales, buildup of the diffusion layer causes a shift from a linearly dominated to a radially dominated diffusion regime, which causes another deviation from linearity.
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that is planar but can also be derived for spherical, cylindrical, and rectangular geometries by using the corresponding
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Bard, A. J.; Faulkner, L. R. “Electrochemical
Methods. Fundamentals and Applications” 2nd Ed. Wiley, New York. 2001.
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Cottrell, F. G. (1903-01-01). "Der
Reststrom bei galvanischer Polarisation, betrachtet als ein Diffusionsproblem".
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sometimes indicate that the redox event is associated with other processes, such as association of a
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63:/ferrocenium couple, the current measured depends on the rate at which the
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47:. Specifically it describes the current response when the potential is a
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177:= number of electrons (to reduce/oxidize one molecule of analyte
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diffuses to the electrode. That is, the current is said to be "
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Variation of current density following the
Cottrell equation
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is the collection of constants for a given system (
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197:= area of the (planar) electrode in cm
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447:(1). Walter de Gruyter GmbH: 385.
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81:Fick's second law of diffusion
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519:. You can help Knowledge by
338:{\displaystyle i=kt^{-1/2},}
16:Equation in electrochemistry
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51:in time. It was derived by
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53:Frederick Gardner Cottrell
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380:{\displaystyle c_{j}^{0}}
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171:= current, in units of A
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515:-related article is a
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244:{\displaystyle j}
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274:= time in s.
264:for species
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406:Voltammetry
560:Categories
427:References
251:in mol/cm;
471:2196-7156
317:−
143:π
73:electrode
61:ferrocene
41:potential
400:See also
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351:n, F, A
268:in cm/s
164:where,
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94:i
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