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cyclic voltammetry of ferrocenecarboxaldehyde

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:

working electrode: platinum wire, 0.25mm diameter
counter electrode: platinum wire, 0.25mm diameter
reference electrode: none
solvent: acetonitrile
electrolyte: ferrocenecarboxaldehyde
support electrolyte: tetrabutylammonium hexafluorophosphate
scan rate: ~600mV/s

Platinum wires each have a submerged length of about 2mm to 5mm and are separated by about 2cm. I was previously using tetrabutylammonium iodide, but that is probably not a good support because the iodide ions will become iodine and forming a blocking layer on my electrode?

I also tried using graphite rods as the electrodes but obtained similar poor-looking CV shapes.

graphite rods

What should I change to obtain the standard CV shape of an outer-sphere redox species?

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    $\begingroup$ For starters, you might want to try a much lower scan rate—maybe 50 mV/s, and it would be helpful to know the concentrations of your analyte and supporting electrolyte. The area of the counter electrode should also be much larger than that of the working electrode in most cases, so try submerging it more or coiling it. $\endgroup$ – Michael DM Dryden Jan 12 '16 at 23:46
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Without a proper reference electrode, knowing what potential your ferrocene/ferrocenium couple will show up is quite impossible. You should sweep a larger potential window, until the solvent breakdown potential on either end.

As Michael Dryden suggested, you should sweep slower as well. That will help with the signal getting resolved easier.

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