Silver Plating Over Gold Electrodes

[ealonas]

Hello,

I have two quesitons regarding the silver plug plate kit. I am attempting to plate silver onto one electrode (gold plated on copper, 0.17" x 0.09" surface dimensions) that is part of a three electrode set (also gold on copper, part of a printed circuit board) using the pnp (stainles steel wand 1.7V power supply) with immersion of the electrodes in a small volume (100uL) of silver solution. Right when I pour the silver solution onto the electrodes, not only the electrode I want to silver plate, but all three gold electrodes get plated with silver without applying any power to the circuit. When I actually apply power to the circuit, the electrode I want to plate silver turns black almost instantly. What can I do to get a nice silver coat on only one of the electrodes?

Thanks,
Eric Alonas
Undergraduate Researcher
Biodesign Institute
Arizona State University
eric.alonas@asu.edu

[ashcroft01]

ealonas,

Not exactly sure of what you mean by three electrode set without a photo of it, but I am picturing in my head what I think that it would look like.

You are speaking of plating onto a printed circuit card, correct?

Are all three electrodes conductive with each other or are they electronically isolated?

There may be a small electrical charge in the card itself from any installed devices (capacitors, diodes, etc.) that may cause a bleed off of stray voltage to the electrodes allowing all three of them to plate when immersed.

When immersion plating, everything that is conductive with the cathode will get plated just the same.

The best method of achieving a single electrode plating would be to brush plate just the one that you would like silvered. This will keep it isolated from the other two if you make the connection close to where you will terminate the electro-plate.

If the wand and bandage set up is too wide or large, then try one of the pen plating wands.

I hope that this information was helpful.

Best of luck,