My friends calculating the surface area of the electrode using CV follow this paper:

http://www.sciencedirect.com/science/article/pii/002207289280162W

Using randles Sevcik equation and performing CV at different scan rates, you can calculate easily your active surface area. Just be sure to use the right diffusion coefficient of your probe.

First you should select a potential scan range where the Faradic current on your electrode is negligible, in this way the current you measure will correspond only to the charge/discharge of the electric double layer. Next you can apply a series of scan rates in order to built next a plot  of I vs. scan rate at a fixed potential. If the plot is linear, the slope will give you the capacitance of the double layer of your electrode (in Farads). The nature of your electrode (Pb, Hg, carbon, etc...) corresponds to a given specific capacitance of EDL in F/cm² which can be found in the literature. The surface of your electrode will be then the ratio between the capacitance you get from the CV measurements and the literature value of the the specific capacitance of EDL.

If you have considerable Faradic currents in the potential scan range, than you should try to separate the Faradic and the capacitive currents. Once you get your the capacitive component, you can apply the above-mentioned methodology.

The most commonly used method is to use the Randles-Sevcik expression of a well-known chemical system such as the couple 1 mM [Fe(CN)6]3-/4- in 0.1 M KCl. You can check the link below for more information.

Obviously you can use any other chemical system if you know all the  parameters required to use the R-S equation. It depends on the nature of your electrode.

Note that there are different equations for reversible, irreversible and quasi-reversible processes.

http://www.sciencedirect.com/science/article/pii/S0013468606003689

Hi all,

I have check the Randles-Sevcik Equation but it needs the DLi, to compute the surface area.

But the equation I am using to solve the DLi also needs the surface area?

hi,

I got the surface area of modified electrode 3.58 cm2; is it logical? by cyclic voltammetry in hexacyanoferrate

Calculation of the real surface area is dependent on the material of the electrode. The literature contains some specific examples.

For platinum you can integrate the area under hydrogen adsorption or desorption or you take the average of both and you equate it to a certain number of atoms based on the assumption that one hydrogen atom is bonded to one platinum atom.

Other methods are based on charging current . The following paper is very useful.

Journal of Electroanalytical Chemistry

Volume 327, Issues 1–2, 10 June 1992, Pages 353-376📷

Real surface area measurements in electrochemistry

https://doi.org/10.1016/0022-0728(92)80162-W

It depends on the cyclic voltammogram you obtained. If you are working with reversible reaction, Randles Sevcik equation is used for determining the effective surface area. You need to know the diffusivity of the active species, the concentration of the active species and the faradaic peak current from your cyclic voltammogram.

However, if the reaction you considered is irreversible, the relation of Nicholson and Shain should be applied instead. You need to know the charge transfer coefficient, which can be calculated using the peak potential and half peak potential.

If it is quasireversible, you need to correct the faradaic peak current to be the reversible peak current first by the relation of Matsuda and Ayabe (after that apply it with Randles-Sevcik equation). Using this relation you need the reaction rate constant, which can be calculated by Nicholson's method.

If your cyclic voltammogram contains the charging current (usually governed by a CPE, not a capacitor), the difficulty of estimating the effective surface area is finding the faradaic peak current.

This paper might help

Article Ohmic resistance and constant phase element effects on cycli...

electrode material and shape led to area of electrode

Using the formula ECSA = Cdl /Cs electroactive area can be estimated.

AbidbUllah, Sure,

First of all take a CV at 10 mV within a broad potential window, here you can see several regions of CV, such as metal redox region, OER, HER, and hydrogen reduction region as well in case of Pt-based electrodes. A region somewhere in between hydrogen reduction and metal redox reaction, where there will be not any faradaic contribution will be of your interest. Take few CVs in the above non-faradaic potential region of CV . Further optimization of the potential window may be needed to have a rectangle shape CV. Now, take several CVs at various scan rates such as 2,5,10, 20, 30, 40, 50, or more.

Following this, identified a potential value in the middle region and the current values associated with this potential value should be plotted as a function of scan rate. The slope of which gives the value of double-layer capacitance according to the equation below

ic= νCdl

where ic is the double layer charging current, ν is scan rate and Cdl is double layer charging capacitance. The electrochemically active surface area is calculated from the following relation

ECSA=Cdl/Cs

Here, Cs signifies the double layer of smooth catalytic surface deposited on the conductor surface. The values of specific capacitance for solid metal electrodes with or without immobilized electrocatalysts have been reported in the literature for acidic to alkaline media. The value for metal electrodes in alkaline electrolytes lies in the range from 0.022 to 0.130 mF cm2- in the KOH solution. One can consider an optimized value of 0.035 mF cm2- (0.035 or 0.040 is normally reported for Ni, Co, Cu , Fe metal-based electrodes in literature, it merely depends on type of electrode you are using, for more details please follow the link Article Benchmarking Heterogeneous Electrocatalysts for the Oxygen E...

Article Spray-Coated Thin-Film Ni-Oxide Nanoflakes as Single Electro...

Noorulain Babar ECSA=Cdl/Cs, so wihout unity ?

Hello everyone, If anyone could please kindly help me out in finding how to calculate surface area of a hybrid electrode (combination of stainless steel and carbon cloth) using CV technique? Noorulain Babar Mohammed Hourani Juan Daniel Mozo Ангел Кирчев

Salem Nasraoui ECSA= Cdl in mF/ Cs in mF/cm2

@sadaf shakeel, procedure is same as mentioned above. Please follow it and let me know if you're not getting results.

Noorulain Babar thank you mam. I am just confused in one step Cs of carbon cloth and stainless steel. Should i calculate Cs using charge discharge curve and then put it in the above equation?

Did you check that menuscript attached above by McCrory et al. ?

@Sajid Rauf please read the attached article

https://pubs.acs.org/doi/abs/10.1021/acsomega.9b00807

If you need any guidance feel free to contact.

Good luck

Noorulain Babar I didn'd getting correct result . suffering by some unit issues. if possible please help me to calculate specific capacitance for my material

It'Ok. Please let me know your material.

Simply convert all the parameters to SI units, then perform the calculations @arunkumar Gunasekaran

I think we have to take the material of the electrode in consideration. For platinum electrodes, polycrystalline or single crystal electrodes, the cyclic voltammogram is run and the area under the i-E curve in the hydrogen region is integrated and calculated. The charge underneath the i-E curve for hydrogen adsorption and desorption is calculated and related to the real surface area through the charge equivalent reported in the literature.

Or in general as it is reported and mentioned by some people, through the charging current.