Platinum Plating - Best Method(s)?

[InspectorTaylor]

I'm looking for an easy (or least complicated) method for plating Titanium and Stainless Steel with Platinum. Everything I've found so far seem to be fairly involved complex methods but surely there must be a fairly down and dirty "backyard" method that would work good enough for what I need.

I'm trying to make some electrodes for use in water electrolysis that won't be consumed in the process. Since Platinum isn't cheap I've had to be resourceful. Hard drive platters turned out to be perfect candidates for experimenting with platinum. They can work great used as they are and plates or for recovering the platinum to use in plating other things. I can get the platinum foil off of the platters easy enough, and have played around with dissolving the foil in nitric acid and get a pretty green solution, but now what? Can I use that solution as the bath for the plating process or is that too easy to work? Also, does the piece I want to plate need to be the cathode or anode and what should I use for the other electrode? Any sugestions?

Thanks!

 

[tomwalz]

Yahoo has an electroplating goup that discusses a lot of this sort of thing.

http://tech.groups.yahoo.com/group/Electroplating/

Thomas J. Walz
Carbide Processors, Inc.

http://www.carbideprocessors.com

Good engineering starts with a Grainger Catalog.

 

[MagMike]

How thick a coating do you need? If it's just a few hundred microns, you may want to consider a physical vapor deposition (PVD) process like sputtering. If I'm not mistaken, that's how they apply the coating onto hard disks. If you do a Google search for "sputter platinum services" you'll find a few places.

 

[ornerynorsk]

Have you heard of Caswell Plating? They cater to the home shop plater.

http://www.caswellplating.com

 

[InspectorTaylor]

Platinum shouldn't technically be consumed during electrolysis so the coating wouldn't need to be very thick, it would be more important that it was evenly distributed enough to cover the entire part being plated so its protected from being attacked by the electrolyte solution.

Ultimately I'd like to be able to plate some stainless spheres that are .093" in dia. I'd like to see how well a cell would work if you made the electrodes as a mass of spheres instead of the usual plates, rods, screens, or wires you always see being used. You could call it something like a pebble reactor. LOL

There's several different configs I'd like to try out, one being where the there are just the positive and negative electrodes consisting of the spheres, another setup like the one I just described but with a third group of spheres between the electrodes mimicking a neutral plate. Lastly, instead of one bunch of spheres between electrodes, a meticulously layered cell using a single layers of spheres separated by a nonconductive mesh. The first layer on each end of the stack would be electrodes of the same polarity and the opposing electrode would be the single layer at the center of the stack. The idea being that each separated layer between the layers that are used for the cathodes and anode would be the neutral layers.

My theory is that spheres have the best shape for creating electrodes and a cell with just the right design using spheres will make a more efficient electrolyzer than any other type. The reasoning being that spheres maximize surface area and have the ability to create a neatly organized, densely packed masses that remain porous allowing gas bubbles to escape and electrolyte to easily flow through it and have no sharp edges for current to bleed off of. That's my theory anyways.... I just need to figure out how to plate things with platinum using what I have around the house and I know with all the crap I have I can do it, heck I'm already half way there, I just need that last piece of the process... getting the dissolved platinum back onto what I want plated.

I'll have to go check out that link to the Google forum. Thanks for the link!