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How to calculate overpotential from HER LSV curve?
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Les McLean
How to calculate overpotential from HER LSV curve?
Based on your graph and formula the reading against your Ag//AgCl electrode is -1.8 V. Is it correct? Ag/AgCl electrode is not recommended for strong basic solutions.
Based on your graph and formula the reading against your Ag//AgCl electrode is -1.8 V. Is it correct? Ag/AgCl electrode is not recommended for strong basic solutions.
Hw did you measure the RHE potential, what is you elecrolyte concentration and nature, what is your reference electrode, Also it seems that you have two redox species insteed of hydrogen Hrr
Hw did you measure the RHE potential, what is you elecrolyte concentration and nature, what is your reference electrode, Also it seems that you have two redox species insteed of hydrogen Hrr
Nice sir @ Yurii V Geletii. I want another point. Why we have not to use Ag/AgCl reference electrode in electrolytes with higher pH? And then which type of reference electrode is most suitable for this study? So that i will repeat the whole experiment with the new conditions you have proposed.
Nice sir @ Yurii V Geletii. I want another point. Why we have not to use Ag/AgCl reference electrode in electrolytes with higher pH? And then which type of reference electrode is most suitable for this study? So that i will repeat the whole experiment with the new conditions you have proposed.
There is no strict definition at what current to measure over potential. The linear increase of the current might be due to the capacitance current or reduction of electrode material., or whatever else. Try CV with several cycles. Start from the rest potential to negative direction, don't apply potentials higher than the rest one. The peak around +0.5 V is very suspicious.
There is no strict definition at what current to measure over potential. The linear increase of the current might be due to the capacitance current or reduction of electrode material., or whatever else. Try CV with several cycles. Start from the rest potential to negative direction, don't apply potentials higher than the rest one. The peak around +0.5 V is very suspicious.
Bezzi Hamza thanks for your answer to my question. RHE potential was measured by =Potential (Ag/AgCl)+0.197+(0.059*14). 1 M KOH was used as electrolyte. It was alkaline in nature. Ag/AgCl was reference electrode.
Bezzi Hamza thanks for your answer to my question. RHE potential was measured by =Potential (Ag/AgCl)+0.197+(0.059*14). 1 M KOH was used as electrolyte. It was alkaline in nature. Ag/AgCl was reference electrode.
I am again thankful to @yurri V Geletii for helping young researchers at this platform with his precious experience. I have found a large number of manuscripts using Ag/Agcl reference electrode in 1 M KOH solution. So that i have used. Definitely, 1.68 v vs Ag/AgCl is the onset potential and 1.73 v vs Ag/AgCl as overpotential to attain a current density of 100 mA/cm2. My question was that, i am not able to find the overpotential required to attain current density at 10 mA/cm2. Because, before crossing the 0 v (vs RHE) my electrode has attained this current density. What was the problem with my electrode or setup? Why it consumes this too much current before reaching the onset potential?
I am again thankful to @yurri V Geletii for helping young researchers at this platform with his precious experience. I have found a large number of manuscripts using Ag/Agcl reference electrode in 1 M KOH solution. So that i have used. Definitely, 1.68 v vs Ag/AgCl is the onset potential and 1.73 v vs Ag/AgCl as overpotential to attain a current density of 100 mA/cm2. My question was that, i am not able to find the overpotential required to attain current density at 10 mA/cm2. Because, before crossing the 0 v (vs RHE) my electrode has attained this current density. What was the problem with my electrode or setup? Why it consumes this too much current before reaching the onset potential?
Dear Sheraz, I don't think that using Ag/AgCl reference electrode for alkaline electrolytes is a good idea. I would propose to switch to an alkaline reference electrode (like Hg/HgO/ NaOH etc). I also made bad experiences with the Ag/AgCl or SCE in alkaline solutions, while the Hg/HgO/NaOH worked well also over extended time periods (long-time experiments). Best regards, Sajed
Dear Sheraz, I don't think that using Ag/AgCl reference electrode for alkaline electrolytes is a good idea. I would propose to switch to an alkaline reference electrode (like Hg/HgO/ NaOH etc). I also made bad experiences with the Ag/AgCl or SCE in alkaline solutions, while the Hg/HgO/NaOH worked well also over extended time periods (long-time experiments). Best regards, Sajed
Based on your graph and formula the reading against your Ag//AgCl electrode is -1.8 V. Is it correct? Ag/AgCl electrode is not recommended for strong basic solutions.
Based on your graph and formula the reading against your Ag//AgCl electrode is -1.8 V. Is it correct? Ag/AgCl electrode is not recommended for strong basic solutions.
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Hw did you measure the RHE potential, what is you elecrolyte concentration and nature, what is your reference electrode, Also it seems that you have two redox species insteed of hydrogen Hrr
Hw did you measure the RHE potential, what is you elecrolyte concentration and nature, what is your reference electrode, Also it seems that you have two redox species insteed of hydrogen Hrr
More
VOTE
Nice sir @ Yurii V Geletii.
I want another point.
Why we have not to use Ag/AgCl reference electrode in electrolytes with higher pH? And then which type of reference electrode is most suitable for this study? So that i will repeat the whole experiment with the new conditions you have proposed.
Nice sir @ Yurii V Geletii.
I want another point.
Why we have not to use Ag/AgCl reference electrode in electrolytes with higher pH? And then which type of reference electrode is most suitable for this study? So that i will repeat the whole experiment with the new conditions you have proposed.
More
VOTE
There is no strict definition at what current to measure over potential. The linear increase of the current might be due to the capacitance current or reduction of electrode material., or whatever else. Try CV with several cycles. Start from the rest potential to negative direction, don't apply potentials higher than the rest one. The peak around +0.5 V is very suspicious.
There is no strict definition at what current to measure over potential. The linear increase of the current might be due to the capacitance current or reduction of electrode material., or whatever else. Try CV with several cycles. Start from the rest potential to negative direction, don't apply potentials higher than the rest one. The peak around +0.5 V is very suspicious.
More
VOTE
Bezzi Hamza thanks for your answer to my question.
RHE potential was measured by =Potential (Ag/AgCl)+0.197+(0.059*14).
1 M KOH was used as electrolyte.
It was alkaline in nature.
Ag/AgCl was reference electrode.
Bezzi Hamza thanks for your answer to my question.
RHE potential was measured by =Potential (Ag/AgCl)+0.197+(0.059*14).
1 M KOH was used as electrolyte.
It was alkaline in nature.
Ag/AgCl was reference electrode.
More
VOTE
I am again thankful to @yurri V Geletii for helping young researchers at this platform with his precious experience.
I have found a large number of manuscripts using Ag/Agcl reference electrode in 1 M KOH solution.
So that i have used.
Definitely, 1.68 v vs Ag/AgCl is the onset potential and 1.73 v vs Ag/AgCl as overpotential to attain a current density of 100 mA/cm2.
My question was that, i am not able to find the overpotential required to attain current density at 10 mA/cm2. Because, before crossing the 0 v (vs RHE) my electrode has attained this current density.
What was the problem with my electrode or setup? Why it consumes this too much current before reaching the onset potential?
I am again thankful to @yurri V Geletii for helping young researchers at this platform with his precious experience.
I have found a large number of manuscripts using Ag/Agcl reference electrode in 1 M KOH solution.
So that i have used.
Definitely, 1.68 v vs Ag/AgCl is the onset potential and 1.73 v vs Ag/AgCl as overpotential to attain a current density of 100 mA/cm2.
My question was that, i am not able to find the overpotential required to attain current density at 10 mA/cm2. Because, before crossing the 0 v (vs RHE) my electrode has attained this current density.
What was the problem with my electrode or setup? Why it consumes this too much current before reaching the onset potential?
More
VOTE
Dear Sheraz,
I don't think that using Ag/AgCl reference electrode for alkaline electrolytes is a good idea. I would propose to switch to an alkaline reference electrode (like Hg/HgO/ NaOH etc). I also made bad experiences with the Ag/AgCl or SCE in alkaline solutions, while the Hg/HgO/NaOH worked well also over extended time periods (long-time experiments).
Best regards,
Sajed
Dear Sheraz,
I don't think that using Ag/AgCl reference electrode for alkaline electrolytes is a good idea. I would propose to switch to an alkaline reference electrode (like Hg/HgO/ NaOH etc). I also made bad experiences with the Ag/AgCl or SCE in alkaline solutions, while the Hg/HgO/NaOH worked well also over extended time periods (long-time experiments).
Best regards,
Sajed
More
VOTE