Based on the data from my first experiments, where the carbon fibers pruduced were around one micrometer thick and curled up, I constructed an improved experimental setup where I use
- Alumina crucible instead of steel one => less iron
- Fresh lithium carbonate instead of reusing same => less lithium oxide
- New cathodes with thicker layer of zinc
- Longer initial, low current phase
Based on the inspirational article I’ve used for the experiments, both iron and lithium oxide would make the carbon fibers curled, so alumina and fresh lithium carbonate should fix those issues. The other two changes were because I felt that it might be better this way.
The drawback of using alumina crucible is that you need to heat it up slowly (first 2.5C/min, later 5C/min) so that it doesn’t break from heatshock. That’s quite tedious as you need to be switching the induction stove on and off every couple of minutes for the first hour and a half. The alumina crucible was sitting inside the steel pot with some sand in between for smoother heating. I managed to break the crucible every time though, I hope that this doesn’t mess up my results…
Anyways, I managed to run a couple of experiments with this setup and would now need to send the samples to a lab to get SEM pictures of them. Let’s see when I manage to arrange this.
I noticed one thing immediately though: now the nickel anode gets quite corroded while previously there was almost no effect on it!