Good question. I know little. Except that there are a large number of variables to play with -- substrate, concentration, current density,
temperature, agitation, surfactants, impurities and the presence of other ions.
My copper electrode is built up on a copper wire and is quite a dense solid mass. It looks ugly since I did a bit of electrolysis with carbon anodes
and so it has fine carbon dispersed throughout. I get a small amount of Cu powder deposit but that is really minor. I don't get long dendrites but I
guess the copper is probably dendritic on a smaller scale.
If I was aiming for a particular form, I would read the literature and follow a recipe.
My intention at some stage is to electrorefine my ugly electrode and produce a cleaner and more pleasant-looking copper sample for the element
collection. So... if you come across a method that results in beautifully-formed crystals, I am interested.
As for the CuO thermite -- it's all over in a few seconds. It would easily be mistaken as a dust cloud -- perhaps sawdust unless you were up close.
In a windy day, there would be perhaps a 20 second opportunity to notice something suspicious. For a small thermite you should get away with it
fairly easily. |
