Talk:Overpotential

I have increased the importance of this article as the concept of overpotentiail is key to understanding why simple predictions using standard electrode potentials often fail.--Axiosaurus (talk) 09:45, 23 February 2009 (UTC)

Activation overpotential

Isn't this a practical term for the difference between the thermodynamically derived PD and the PD required for useful current to flow in a real world electrolytic cell. It therefore is a summation of all of the other types of overpotential involved- e.g. reaction OP, concentration OP etc.--Axiosaurus (talk) 10:05, 23 February 2009 (UTC)

I think their has been some confusion in the table of activation overpotentials - it would be good to define the temperature, electrolyte and current density (typically 1 mA/cm²). I think the value for Fe look more like the Tafel slope (0.15 V) than the overpotential (usually closer to 0.5 V)? 81.223.140.162 (talk) 15:00, 8 August 2011 (UTC)

I've updated the overpotentials table to contain published data for hydrogen and oxygen evolution. The new reference (DOI: 10.1002/anie.202005745) gives temperature, electrolyte, current density information for the measurements, which would probably be best added as a footnote. 86.31.133.189 (talk) 09:25, 8 July 2020 (UTC)

Electron transfer overpotential, Diffusion overpotential and back e.mf ?

I hacve come across these in the past as "reasons " for overpotential- they are mentioned in other text books.Where do they fit in? --Axiosaurus (talk) 10:08, 23 February 2009 (UTC)

Overvoltage

Is this the same thing as overpotential?--Axiosaurus (talk) 10:16, 23 February 2009 (UTC)

The language often gets muddled, with voltage and potential used interchangeably in many situations. Charge, current, coulombic, and faradic get swapped around in a similar way. The only problem with calling overpotential by the name overvoltage is that overvoltage has another defined meaning as explained by its article.--156.40.228.192 (talk) 17:46, 2 March 2009 (UTC)

overpotential table(s)

This is the only table of overpotentials I've found, and it's very useful for understanding the effect. However, it seems to be for acid solution and contains only a few example elements, which is no specific help for (eg) salt or alkaline battery development. If they exist (my searches have been pretty fruitless), I'd love to see extended tables or links to tables with more info. 24.69.167.69 (talk) 22:30, 29 December 2011 (UTC)Craig Carmichael

Table has been updated to include figures from primary literature. The given reference (DOI: 10.1002/anie.202005745) confirms these figures are for aqueous solution (predominantly, this is 1 M hydrochloric or sulfuric acid for hydrogen evolution overpotential measurements, 1 M potassium hydroxide for oxygen evolution measurements), although the reference also gives figures for measurements in methanol. There is also hydrogen evolution data for a few additional materials given, but to keep the table to a reasonable size I haven't added them at this time. 86.31.133.189 (talk) 09:32, 8 July 2020 (UTC)