Hello Harsh Kumar

The geometric area differs from the actual electrode area.

The geometric area is just the macroscopic area measurement operation.

The real area is based on a surface adsorption model, and can be investigated by symple chronopotentiometry experiments. The real area considers surface adsorption from the macro to the sub-nanometric scale.

A suggestion for a reference:

Determination of the Real Surface Area of a Screen-Printed

Electrode by Chronocoulometry. Int. J. Electrochem. Sci., 7 (2012) 6214 - 6220

Surface area of the electrode can be defined as electroactive surface area which could be calculated by Randles sevick equation by using simple cyclic voltamograms of Ferricyanide system. kindly refer the following article.

Microchemical journal, 2021, 170, 106672.

https://doi.org/10.1016/j.microc.2021.106672

For Screen Printed Electrode the Electroactive Surface Area (ESA) can be determined using the Randles-Sevcik Equation. You should perform a Cyclic Voltammetry of the electrodes in potassium ferrocyanide at different scan speeds, plot the square root of the scan speed vs the intensity of the peak, and using the equation, you can determined the ESA. In the material and method of this paper, you can find the procedure

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