I'm using a stainless steel shim as WE (bare now, with SAMs once I can observe redox peaks). Graphite foil CE, Ag/Ag+ RE. Tried using various redox probes at 1 & 10 mM concentrations. Only observing what appears to be electrolysis of solvent - or perhaps water impurities (testing in hood, not glove-box). Do I need glove-box to see redox peaks or am I doing something else wrong?
First of all, LiClO4 is air sensitive salt. I dont know how did you prepare the solution. It reacts pretty quick with moisture (>20 ppm is enough to poison the salt) and produce acidic environment which could cause TM dissolution. Second, which TM redox behavior are you expecting to see? Concentration wise I do not think you will have problem. I saw 3.3mM Ferrocene peaks in non aqueous media but in glove box. Stainless steel I am not sure how pure it is. Why dont you use GC? let me know if you have further questions.
Thanks Mehmet! Can you recommend an electrolyte that's less moisture-sensitive? LiPF6? TBAPF6?
All these Li based salt would have such sensitivity. May be Na or K counterparts, but you should check.
What is the area of the working electrode? If it's too large you will not see the expected peak behavior.
Iromie, the area is ~2 cm2. I assumed that a larger WE area would provide larger magnitude of redox peak charge.
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