Your platinum deposit is diluted in the CV of carbon. That is normal. If you increase the amount of platinum deposited you may see something.... but no promises!

Sir, I really appreciate about your comment. So I tried to increase the amount of loading amount of pt/c. however i could not find any difference.

Thank you so much for your help. if you have any other idea , please tell me anytime.

Best regards,

Hello Miso, how many CV cycles did you record? Sometimes, Pt NPs need some time to "clean" themselves in the electrolyte solution and to appear on the CV. Otherwise, you might check your grafting method, maybe there is some problem with the synthesis or attachment of the Pt NPs on GC electrode.... Hope you will find solution

@Milutin Smiljanic

Hello sir.

As a cleaning process, I tried 10 CV cycles before. Do I need more cycles? Also, my sample was commercial pt/c. So the other thing that i can check might be an attachment process. ..

I really appreciate for your time.

Hi Miso,

Sometimes 10 cycles are enough and sometimes not, but you can try to increase the number, it should not hurt. Yes, you should check your attachment procedure as well.

You can only get the well-known regular voltammogram under ultraclean condition. The electrode must be very clean, the supporting electrolyte must be very clean and the purging gas must be very clean too. Failure to establish clean conditions gives real hard time.

@ Milutin Smiljanic , @ Christian Lupó @ Mohammed Hourani

Thank you sir. Thanks to your advices, I ran 50 cycles of CV for cleaning.

At first, I found very small peaks. However, as the cycle continued, the peak gradually disappeared. Does this mean that CV cleaning is not a key factor?

Best regards,

I think, the surface area of Pt wire "counter electrode" has not enough size. The counter electrode area must be same or more higher than the working electrode surface area. What is the CE surface area?

I remember making a lot of CV on Pt/C. I do not remember observing the platinum peaks in the CV of this composite. I remember having the same response Miso is having. Does anyone have a paper to see how is this CV supposed to be? I think CV is not to characterize the Pt load. Miso, I found this Article Carbon monoxide oxidation on Pt-Ru electrocatalysts supporte...

@Omar

I read the paper that you found for me. Thank you for your kindness.

As you can see in Fig 4,5 , we can find the hydrogen peak around 0.1-0.2 V (V RHE) at the graph of Pt/C sample. Also, the author described like this in the paper: "The Pt/C E-TEK material shows the typical behavior for this material in acid medium and it does not show the peak at 0.18 V due to the oxidation of hydrogen in the submonolayer. "

@Murat

Hello Mr. Farsak. I can found the surface area of GCE. however i can't found for CE. cause it is a wire - shaped. it seems like a lead for sharp pencil.

Miso,

Maybe gradual disappearance of peaks indicate that your grafting method is not effective enough. Maybe it means that with cycles you are loosing your Pt particles by dissolution? When I was working with Pt NPs, i obtained quite clean and reproducible CV with all features of Pt.

Best,

Milutin

you can increase the surface area if you making the corrugated wire

Miso,

Electrochemical cleaning by cyclization of the electrode potential between the anodic and cathodic potential limits is effective for cleaning the surface of the electrode from adsorbed species only. if the impurities in the bulk there is no way to get red of them by cyclization .

I suggest to follow a very structured procedure to get the well-known cv for platinum.

1. Start with very clean conditions for the cell, the solutions and the purging gas. In this regard all your glassware must be cleaned by immersion in chromic acid solution.

2. The platinum wire must be cleaned by immersion in freshly prepared chromic acid solution after polishing with alumina powder and sonnication fo rfew minutes.

3. Electrochemical cleaning by cyclization

between the anodic and catodic potential limits.