Display MoreFor what it's worth, I'm currently repeating another test this time using 0.125M KOH (so far at 0.5A constant current). The distance-dependent voltage effect still works, and of course no plating is occurring under these conditions.
I got a few times in a row measurements similar to the "after a while" numbers I posted earlier, i.e. approximately:
0.1 mm = 460 mV
0.2 mm = 42 mV
0.3 mm = did not work
However when voltage at 0.1mm dropped to about 150 mV I couldn't manage to measure anything at 0.2 mm. If the signal only proportionally decreased over time, I would have expected to measure values around 10 mV. Again, take this information with a pinch of salt since the mica sheets may have some variations, and results may change depending on consistency of measurements/plates and sheet location and so on. I observed a similar behavior earlier on, though.
Thanks can . Yes, no worries, I've got plenty of salt to throw around 🤣 .
Using the numbers you just gave would give a mean free path of 0.1mm - same ballpark.
I'm curious to see with Alan Smith in the coming weeks whether our bigger plates show similar distance relationships.