I want to perform a three electrode experiment in a non-aqueous electrolyte using a platinum pseudo reference electrode.
1) What is the procedure for using ferrocene to calibrate my platinum reference electrode? Can I just add ferrocene to my electrolyte?
2) How do I compare my measured potential vs Fc/Fc+ to the standard hydrogen electrode? It is my understanding that the Fc/Fc+ redox potential vs SHE will depend on the solvent used, so do I need to measure this on my own?
So, yes, you can add Fc to the electrolyte and measure, then you use that potential as the reference point. As per your 2nd point, reference potentials are solvent dependent so, while you can look at the Fc/Fc+ value vs. SHE (or SCE, or Ag/AgCl) it is better to reference to the known couple in your electrolyte, so you would actually state your potentials vs. Fc/Fc+ in [solvent/electrolyte system].
That said: platinum is not a very good quasi-reference electrode (QRE) if you are in aprotic solvent (and even in, say, aqueous systems, it is better in acidic conditions than alkaline). Metals that have a stable metal oxide to be in equilibrium with have more stability as reference electrodes. This is why so many electrochemists who do use QREs tend to prefer silver.
Jacob, thanks for your answer. In that case I will think about using silver wire instead of platinum.
The other problem is that I want to adjust the composition of my electrolyte by adding a little water, and see how that affects the redox potential at my working electrode. Of course, like you said, the reference electrode potential is solvent dependent, so I won't be able to compare the voltage between my electrolytes.
What do you think about using an aqueous Ag/AgCl reference electrode in my organic electrolyte? I have heard that the cross-contamination of solvent is very slow. If the potential drift is less than 10 mV per day then that would be okay for my work.
Really depends on your solvent. I occasionally used aqueous Ag/AgCl in MeCN but wouldn't try with, say, DME. Still, that isn't really ideal, and making use of a reference designed with organic solvents in mind is a better option (e.g. Ag/Ag+ type).
I want to use EC/DMC electrolytes (for non-aqueous batteries). If I use a Ag/AgNO3 reference electrode, what electrolyte solution do I use? I have seen it used with acetonitrile solvent, but not with carbonates. I imagine there would still be a junction potential and risk of contamination.
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