Nickel(III) reduction in electrolysis?

[Latsabb]

I ordered in chemicals for doing some electrolysis work, one of which was Nickel Oxide. I didnt think to check if it was NiO, or Ni2O3. I was supposed to be using NiO for the Ni2+ ions, but I am curious how this would work out with Ni3+ ions? Will Ni3+ still reduce in the same manner as Ni2+? I was digging through some previous work, and saw a couple of places using 2Ni3+ + 2e- -> 2Ni2+, which made me think that it would reduce and plate in two steps. First going from 3+ to 2+, and then plating on.

Does anyone know? Normally I would just give it a shot, but the rest of the electrolyte composition is too expensive for me to try and toss for no reason.

 

[TeethWhitener]

Are you following a recipe for this electrolysis? NiO is pretty insoluble. If I were doing nickel electroplating (and not following a recipe), I'd start with a soluble salt like NiCl₂. To answer your question, I doubt you have nickel(III) oxide; it's pretty rare. But if you can get nickel ions into solution, and if your voltage is high enough, the Ni³⁺ will eventually reduce just like Ni²⁺. But unless you're following a recipe, I'd be inclined to try something other than nickel oxide.

 

[Latsabb]

This isn't for nickel plating as such, and the low solubility is the key, as I need the electrode covered in particles of nickel, not a layer. The nickel is for nucleation sites of a further reaction. And yes, it is Ni(III), black nickel oxide.

 

[TeethWhitener]

I see. Well, most of my original comment still applies. I don't know what the kinetics of reduction of Ni(III) to Ni(II) is, so I can't say for certain whether you'll get the desired results. The standard reduction potential will only take you so far. If there's a kinetic barrier, the reduction will require an overpotential which is highly dependent on everything going on in the electrolysis bath. If you're following a recipe, I'd say stick to it (especially if it's from the primary literature--it might not be so easily reproducible otherwise). If you're trying to make something like Ni nanoparticles, there are probably other ways to go about doing that which are easier. I'm not sure how much help you're going to get unless you're much more specific about what you're trying to do.