Hello Liliya Dubyey

Are you working in a 2- or 3-electrode system? Is it an organic medium?

It looks like there is a redox signal from -1.5 V to 0 V. But -4 V to 4 V seems too wide to me, is there a reason why you are trying to scan over this potential range? What scan rate are you using? Have you tried to run your experiment with different scan rates?

I would suggest to use a reference electrode first. If you are in aqueous media the common reference electrodes are SCE and Ag/AgCl. However, if you are in organic media, I would suggest to use a platinum wire (isolated inside a glass compartment separated with a frit and containing LiClO4/MeCN) and a silver wire (isolated inside a glass compartment separated with a frit and containing LiClO4/MeCN).

Best regards,

Marie B.

Marie Berthuel Hello

2 eletrode system and not organic medium, and a platinum wire as counter eletrode

can you tell me the difference between two and three eletrode system with a reference eletrode?

We used this wide range because before doing CV we tested our electrochromical film to see if the color would change to blue by apllying voltage, started with just -3/3 V as written in protocol, but the color barely changed so we increased the voltage and the color changed faster and to dark blue. So we did the same in CV.

The scan rate was 0,01V/s

Hello Liliya Dubyey ,

Before further helping you I would like to know what do you mean by PC? When you are using a 2-electrode system how do you connect your system to the potentiostat? Are combining RE and CE cables together and WE alone?

For the difference between the two systems I would suggest to take a look at this RG discussion:

https://www.researchgate.net/post/What_is_the_difference_between_two_electrode_and_three_electrode_photoelectrochemical_characterization

Best regards,

Marie B.

Liliya Dubyey ,

To rephrase the discussion I provided above, in a 2-electrode system, the CE/RE is used to simultaneously act to bias the potential of the cell and also provide a current path.

With a three-electrode system, the addition of a RE allows you to focus on the half-reaction occurring at the WE. The cell is biased w.r.t. the RE, with current flowing between the WE and CE. For characterization, it is highly recommended to use a 3 electrode system.

I would suggest that the potential window is too wide for the substrate and the solution.

Best regards,

Marie B.

Thank you for the discussion link! Very helpful, and I think I should definitely get a 3rd eletrode

PC stands for Propylene carbonate, the solvent used to prepare the eletrolyte

As its my first time working with CV and I just did what my current internship leader said to do, but I can say that I didnt use any of the setup's you mention, only a WE (green colored in this picture) and a CE (platinum wire).

Thank you for your answers!

You are very welcome I hope that your experiment goes well.

Have a nice day!

Best regards,

Marie B.