Questions tagged [cyclic-voltammetry]
Cyclic voltammetry or CV is a type of potentiodynamic electrochemical measurement. In a cyclic voltammetry experiment, the working electrode potential is ramped linearly versus time.
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Is the half-wave potential concentration dependent?
As I was refreshing my knowledge on cyclic voltammetry, I came across the following doubt.
Is the half-wave potential concentration dependent or is it not?
If we look at this graph, let's assume we ...
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Voltammogram during calibration is not smooth
During calibration for differential pulse voltammetry, the voltammogram obtained has two distinct peaks. I am not sure why I am getting two peaks in the range from $\pu{-0.6 V}$ to $\pu{-0.9 V}.$ I ...
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Band gap voltammetry sensors
I'm new in electrochemistry and I am leading with modification of sensors and analytes. I would like to know why the analyte voltammetric signal should be between the band gap of the modifier. If I ...
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Cyclic voltammetry graph of graphite electrode in NaOH
I'm a student who is a beginner to cyclic voltammetry and university electrochemistry in general. For my lab experiment, I performed cyclic voltammetry on a graphite electrode in 1 M NaOH with Ag|AgCl ...
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Why do we have a negative current in cyclic voltammetry curves?
Why do we have a negative current in cyclic voltammetry curves?
here are my thoughts. We have two conventions in reporting data of CV curves: the IUPAC convention and the US convention. In the IUPAC ...
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Applied potential to Saturated silver electrode
I recently did my first cyclic voltammetry. I used a saturated silver reference electrode and two platinum working and counter electrode. This was done with an IKA electrasyn 2.0 device, my parameters ...
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What does the horizontal axis on cyclic voltammograms mean?
In cyclic voltammograms (like the one in the attached image) what exactly is the horizontal axis' voltage refering to? Is it the measured voltage between the reference electrode and working electrode? ...
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onset of oxidation for cyclic voltammetry
I have plotted a cyclic voltagram for my different polymer blends and I am trying to work out the onset of oxidation. picture below is my graph
from this website: https://www.ossila.com/pages/cyclic-...
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How to run electrochemical tests on Microorganism (bacteria in a medium)?
I am trying to run some electrochemical tests(e.g.CV (Cyclic Voltammetry) & EIS (electrical impedance spectroscopy)) using half cell configuration on micro-organisms (e.g.bacteria). The bacteria ...
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What does onset of oxidation mean in Cyclic volammetry
I've read a few posts on here on how to calculate onset of oxidations in Cyclic voltammetry. However, I dont know what it actually means when comparing the onsets of oxidations of two different ...
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Aluminum Battery with PAC setup : Rapid voltage drop problem after a charge
I am a retired man and seek for activity. I dont have background in chemistry but I want to learn an aluminum battery..the known problem is my aluminum metal get eaten and also corrosion even if using ...
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Different solutions in cyclic voltammetry
CV is usually used to monitor corrosion (from what I have learned) because, if it is a reversible reaction, we can see the cathodic and anodic peak in the voltammogram. I know that the scan rate ...
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Cyclic voltammetry for irreversible reactions
I'm new to electrochemistry and I was wondering two things, sorry if these two problems are trivial but I just can't find anything close to this in the literature.
First, the following reaction is ...
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Is my understanding of cyclic voltammetry correct? [closed]
So recently I've been roped into doing some CV and I'm trying to wrap my head around the fundamentals of the science behind it (and electrochemistry more generally! Bare in mind I'm very much not an ...
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clarification on background limits in electrochemistry
I’m teaching myself electrochemistry, and this question is from the general introduction of the book I’m using. According to Bard’s Electrochemical Methods book, in a given cell, the background limits ...
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Electrolytic cell - Potentials
I'm an electronic engineer student and I'm trying to understand the basics of electrolytic cells and practical values' meaning. Based on my figure and electrode potencial values (Vce, Vre and Vwe), ...
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Why is the peak-to-peak separation of cyclic voltammetry is 57 mV?
I'm studying CV, and I wonder if I can calculate the peak-to-peak separation of CV for a reversible redox system.
I found that the separation is 57 mV on my textbook, and my teacher taught me that is ...
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What could be causing my cyclic voltammograms to have a sloped scan?
I am running a CV (cyclic voltammogram) in a two compartment bulk electrolysis cell with pH 7 phosphate buffer (0.5 ion concentration) and a napheon membrane separating the two compartments. I'm using ...
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what should be the onset potential using cyclic voltammetry?
I am working for PEM fuel cell cathode material. I am confused regarding the onset potential determination for my catalyst (CV attached, fig 1 is complete CV while fig 2 is its zoom image for clear ...
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How does cyclic voltammetry in a electrolytic cell measure the precise oxidation potential?
From what I understand, the potential necessary to induce a current to flow in an electrolytic cell depends on both reduction potentials of the anode and cathode reactions, where E(cell) is comprised ...
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What are the factors that affect the redox reactions?
In my work, I used $\ce{Co(OH)2}$ and $\ce{Ni(OH)2}$ as an active materials to fabricate as symmetric supercapacitors in which I used 1-butyl-1-methylpyrrolidinium dicyanamide as an electrolyte.
From ...
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capacitive contribution voltammetry
I am working with a sheet of zinc metal where there is an oxide film on it (ZnO) in passivation conditions (pH=10). I have done voltammetry measurements for different scan rates with a 3 electrodes ...
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Some materials emit more photoelectrons than others - why?
I've been experimenting with some materials by changing the wavelength of the incident light on the material and detecting photoelectrons, like in the diagram below:
I might get a response that looks ...
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Why doesn't fast-scan cyclic voltammetry work with metal electrodes?
Every paper I've seen discussing it uses it with carbon nanofiber or some other carbon material like a diamond. If the physical principles by which it works are based on sweeping through voltages, I ...
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Decreasing magnitude of peaks in cyclic voltammogram?
I'm in an instrumentation course and we covered cyclic voltammetry earlier in the semester and will be doing an experiment in CV next week.
My question is this:
If you have a reaction and sweep the ...
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Cyclic Voltammetry - HOMO and LUMO levels
I'm a physicist, so I apologize if these are obvious questions.
I've carried out CV measurements on a few different types of material (with a ferrocene reference). I am interested in determining the ...
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Why the current of double layer charging is independent of potential?
i-V curve of double layer charging has a rectangular shape. Why when increasing or decreasing the voltage, the current remains constant?
Or I can ask, how the double layer structure is changing by ...
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How could you distinguish between an irreversible electron transfer couple and a chemically irreversible couple using cyclic voltammetry?
What is the difference between an irreversible electron transfer couple and a chemically irreversible couple?
How could you distinguish between these two processes using cyclic voltammetry?
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Voltammetry on homemade supercapacitor
I would like to get some voltammetry curves with my homemade supercapacitor in order to be sure that I have only capacitive effects (capacitive current) in my cell and no redox reactions (faradic ...
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The potential range of the cyclic voltammetry of CoCat in KPi made of D2O
I have a phosphate buffer adjusted to pH 7, and another phosphate buffer made of deuterium oxide (D2O) adjusted to pH 6.6 (pD 7). I want to conduct cyclic voltammetry of cobalt oxide catalyst in these ...
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Selecting a good test solution for Cyclic Voltammetry
So I have a textbook headed my way for this but need to get a head start.
I have a 3-electrode voltammetry setup but I want to test it for some standard values (for educational purposes) before I ...
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Role of the counter/auxiliary electrode in cyclic voltammetry
I am doing a school project on cyclic voltammetry and am currently studying the topic. I have learnt that the reaction mostly takes place around the working electrode where the current is measured ...
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Why is the cyclic voltammetry of my ferrocene compound not showing a standard shape?
I am trying to set-up a new cyclic voltammetry measurement station in my lab but the results are very poor. I am using the following parameters:
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Will oxidation/reduction of copper still occur in an electrochemical cell if it is not in an aqueous environment?
Notation of the reduction and oxidation of copper typically includes the aqueous state. Illustrated below:
$$\ce{Cu(s) -> Cu^2+(aq) + 2e-}$$
This event usually occurs at 0.34 V. What if the copper ...
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How do I write many cyclic voltammetry curves in Nova?
We are making an electrochemical research on supercapacitors that involves checking stability of our material. That requires repeated writing of cyclic voltammetry curves. Our goal is to write at ...
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Why is current non-zero when applied potential is still below E$^0$ in cyclic voltammetry?
In this diagram (Evans et al., J. Chem. Edu.) the current is non-zero, but the potential is still below the normal potential. How can the compound become oxidized at the working electrode, when the ...
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How to find the band gap for a compound?
I have processed a si/polymer hybrid using a silane coupling agent which I need to determine the energy gap / band gap. Would you please let me know the procedure to go about determining the band gap?...
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