Have a look at

https://www.biologic.net/topics/rotating-disk-electrode-how-does-the-levich-analysis-work/

or at the attached document.

dear sir

thanking you

i will read it as well i understand

Dear Chandrasekaran Ramasamy ,

I just want to add that you can either use Cyclic voltammetry and Levich analysis as described in the following documents:

https://www.biologic.net/topics/rotating-disk-electrode-how-does-the-levich-analysis-work/

https://www.biologic.net/wp-content/uploads/2019/08/levich-koutecky-levich_electrochemistry-an56.pdf

But you can also use EIS data fitting to easily reach the diffsion coefficient and it is described here:

https://www.biologic.net/topics/the-easy-way-to-d-the-diffusion-coefficient/

https://www.biologic.net/wp-content/uploads/2019/08/rde-diffusionv_electrochemistry-an66.pdf

I hope this helps,

Best regards,

Nicolas