CV redox peaks and Gamry Potentiometer

In summary, the conversation discusses the use of Gamry Potentiometer for taking CV measurements to find appropriate voltage values for oxidation/reduction peaks, and the use of Echem Analyst for analysis. The CV measurements were performed on a liquid electrolyte to determine if the working electrode accepts Li ions. The individual has questions about interpreting the results, including the absence of peaks at potential differences equal to or below 1V and the possibility of using existing CV measurements to perform Chronoamperometry measurements. They also mention their working electrode being TiO2-Deposited FTO/Glass and using LiClO4-PC aqueous solution as an electrolyte. They have doubts about the reactions kinetics and questions about the redox reactions,
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erbilsilik
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I'm using Gamry Potentiometer for taking CV measurements for finding the appropriate voltage values for oxidation/reduction peaks and Echem Analyst for analyzing. CV measurements has performed on liquid electrolyte in order to find if working electrode accept Li ions. My question is about interpreting the results.

How can I interpret if potential difference equal or below 1V has no oxidation or reduction peak (or has only one of them) while potential sweep between -2V to 2V bring good results but if I change it to 1 to -3 no reduction peak again. Moreover, going to negative values has a bad consequences such broke the working electrode. What does it mean going to negative values?

That was my first question, my second question is: Is it possible perform Chronoamperometry measurements (in other word, simulate) by using existing CV measurements via Echem analyst script editor?
 
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UPDATE TO MY FIRST POST.
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My working electrode is TiO2-Deposited FTO/Glass (thin film). I use LiClO4-PC aqueous solution as an electrolyte. The method is discussed in several papers (doi: 10.1016/0167-2738(86)90214-6). Upon Li+ intercalation due to change in structure TiO2 expected to change a color (from a transparent to grey). However, there is no discernible change in the color that can human eye recognize in my analysis. As a result, I have doubt about the reactions kinetics. So my questions are, as follows.

1) Does seeing a peak in CV curve guarantees that some redox reactions is happening?
2) I've attached a picture of CV curves for various scan rates. Do you agree that it is a quasi reversible system (also discussed in here:https://www.researchgate.net/post/How_to_interpret_CV_redox_peaks_and_is_it_possible_run_a_Chronoamperometry_simulation_from_existing_CV_data ) http://imgur.com/a/hFczu
3) Since current is proportional to scan rate what is the correct way to calculate inserted charges (Qa and Qc -> Integration in Gamry)

4) After a lot of try, I found going to further from -1.7V broke my working electrode. And also, going to away from +1.9V. Can I consider this, as my limitations?

5) What does max current means in CV measurement? Does changing the value effects the shape of the curve?
 
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1. What are CV redox peaks and how are they measured?

CV redox peaks refer to the peaks observed in cyclic voltammetry (CV) experiments, which measure the current response of a redox reaction as a function of applied potential. These peaks represent the oxidation and reduction processes of a species present in the solution, and are typically measured using a potentiostat such as the Gamry Potentiometer.

2. What information can be obtained from CV redox peaks?

Cyclic voltammetry experiments can provide information such as the oxidation and reduction potentials of a species, the number of electrons involved in the redox reaction, and the reversibility and kinetics of the reaction. The shape and position of the redox peaks can also give insights into the stability and nature of the species being studied.

3. How does the Gamry Potentiometer work?

The Gamry Potentiometer is a type of potentiostat that measures the current response of a redox reaction as a function of applied potential. It does this by applying a small voltage to the working electrode in the electrochemical cell, and measuring the resulting current. This voltage can be varied in a controlled manner to obtain a complete cyclic voltammogram.

4. What are the advantages of using a Gamry Potentiometer for CV experiments?

The Gamry Potentiometer offers several advantages for CV experiments, such as high accuracy and precision, a wide potential range, and the ability to control the scan rate of the potential. It also has multiple channels, allowing for simultaneous measurements on multiple electrodes, and can be used for various electrochemical techniques in addition to CV.

5. Are there any limitations to using a Gamry Potentiometer for CV experiments?

While the Gamry Potentiometer is a versatile and reliable instrument, there are a few limitations to consider. These include the need for a stable and well-controlled reference electrode, the potential for noise and interference in the measurement, and the possibility of electrode fouling or degradation over time. Additionally, the accuracy of the results may be affected by factors such as electrode size and geometry, and the presence of other electroactive species in the solution.

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