Talk:Cyclic voltammetry

Untitled

I felt the second sentence at the begining "To obtain a cyclic voltammogram, the voltage is varied in a solution and the change in current is measured with respect to the change in voltage" was kind of misleading on a few levels- "voltage is varied in a solution" doesn't really make sense, and the CV measures current, not "change in current". So I changed it to "In a cyclic voltammetry experiment, a voltage is applied to a working electrode in solution and current flowing at the working electrode is plotted versus the applied voltage to give the cyclic voltammogram." Maybe I'll make some more changes when I read the rest of the article. It's cool that there's electrochemistry stuff on wikipedia. -Scott

Made a few contributions today - and a few changes. Article is good, but as an electrochemist, I would like to modify the page and will be doing so here and there over the next couple of months. I don't know it all - but am rather passionate about the subject, so I feel it's important to be a bit more exact on this page. Thanks! TMPaschkewitz 01:50, 23 January 2006 (UTC)

too complicated

This page is useless for me, someone with no background in this. Links, explanation. TOo technical for a general audience!

The voltammogram figure is a bit confusing to me - is it normal to have larger values on the left!? —Preceding unsigned comment added by 193.137.24.32 (talk) 10:33, 23 November 2007 (UTC)

I agree with the previous comment. Furthermore, the language is imprecise, e.g. "This ramping is known as the experiment's scan rate (V/s)." - no it isn't, the slope of the ramp is the rate. In the next sentence, "the current is measured between the working electrode and the counter electrode" but there is no explanation of what a counter electrode is. I will try to revise this page, but I looked it up in the first place because it is not an area in which I have expertise 96.245.11.102 (talk) 21:49, 5 December 2010 (UTC)

CV is not a hydrodynamic technique

I fixed the hydrodynamic part of things but wanted to explain why I deleted the following text.

Also the term cyclic voltammetry is used to describe experiments in which two immiscible liquids (each one containing a reference and a counter electrode) are in contact. Such a four electrode cell uses the interface between the two liquids as the working electrode.

First of I'm unfamiliar with the technique. I'm sure its useful and interesting but as it stand its not described correctly. First, classic CV is a three electrode technique more complex experiments may resemble CV but are in their very nature something different. Second, there is no way that the surface interface is an electrode since it doesn't directly conduct back to the potentiostate. Perhaps from some perspective it is an electrode but again thats really complex and needs more explanation. I won't speculate on a better way to describe this experiments but if it discussed it needs to be discussed in more detail and referenced.--OMCV (talk) 07:06, 11 April 2008 (UTC)

Potential ramp

The potential ramp shown is characteristic of linear sweep CV, but it's not a characteristic of cyclic voltammetry in general. There are also other ramps, like staircase or square wave. I find this quite misleading. — Preceding unsigned comment added by JPBoyd (talk • contribs) 16:20, 6 March 2011 (UTC)

formal potential vs. half-cell potential

It ist not the half cell potential that is measured by cyclic voltammetry, the potetnial is known as formal potential. It cannot be, because the half-cell potential E⁰ is found at equal concentrations of reduced and oxidized form, this is usually not the case in such experiments. You can easily check this by measuring a CV of ferrocene vs. a Fc/Fc+ electrode in acetonitrile or K4FeCN6 vs. a K3FeCN6/K4FeCN6 electrode in water. — Preceding unsigned comment added by JPBoyd (talk • contribs) 16:26, 6 March 2011 (UTC)

CV image at the start of the article has one axis inverted

one of the axes cannot be correct here -- reduction (going to less-positive potentials) does not give a positive current-- it gives a negative current (i should be negative for e- flowing in)

(either y ^^ and x ^^ both tend to negative (American convention) or both tend to positive (IUPAC convention))

so one of the axes is backwards in the diagram

best, — Preceding unsigned comment added by 79.136.77.190 (talk) 23:13, 22 February 2022 (UTC)

CV and kinetics/scan rate

CV relates to both the thermodynamics of the redox chemistry but also kinetics of electron transfer and mass transport. As such CV contain not just information about the redox couple of the analyte but also the kinetic information of the underlying electrochemical processes. Bard and Saveant have devoted much work with great success to show the utility of CV to extract kinetic information such as observed rate constant. I think a brief discussion on this matter is warranted. FlashNickel (talk) 00:18, 22 June 2024 (UTC)