In theory, the voltage needed to be applied for water splitting is 1.23 V. When I apply 1.23 V, after 10 min system shows amplifier overloaded error so I decreased the voltage. I applied 0.7 V and I see hydrogen bubbles around the cathode ( Platinum as WE).
Water splitting can be achieved at voltage lower than 1.23 V, but with the low yields. 1.23 V is the difference between the standard thermodynamic potential of water oxidation and reduction.
Thank you for the reply Yurii. I give it 4 hours to be run. is this amount of time enough for producing of some amount of measurable Hydrogen at 0.7 V?
I have no ideas about your electrochemical cell, your solution, how do you apply 0.7 V?
Yurii V Geletii , the Reference electrode is Ag/AgCl. Working electrode is Platinum and Counter electrode is Glassy carbon. the electrolyte is 2M KOH. I apply the voltage via an instrument and the software I use is EC lab.
Do your own home-work. Find what is the potential of water reduction at pH 14 versus SHE, Convert it to versus Ag/AgCl. Compare with your potential. Pay an attention to the sign of potential, negative or positive. Check, what reaction takes place in your experiment, water oxidation or reduction.
By the way, Ag/AgCl ref electrode is not recommended for basic solutions.
Yurii V Geletii ,
Thank you for the reply. Only oxidation reaction takes place. I have checked it.
I'm completely confused. You wrote that you saw hydrogen bubbles on Pt-cathode. Now you are saying that only oxidation takes place.
Yurii V Geletii
The software shows on the screen that oxidation process is running but I think this is a software problem and the redox reaction take place at the same time.
I converted the refernce electrode potential from SHE to Ag/AgCl and took an LSV and got the correct voltage.
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