Author Topic: The choice of metal as cathode  (Read 1276 times)

0 Members and 1 Guest are viewing this topic.

Offline PeterXXL

  • Expert
  • Participant
  • ***
  • Posts: 496
  • Likes: 3
The choice of metal as cathode
« on: December 09, 2014, 04:50:15 AM »
What is the reason for using Copper as cathode instead of Silver? As I understand it, Silver have a slightly higher electrical conductivity and slightly lower electrical resistance than Copper. Ref:   http://en.wikipedia.org/wiki/Electrical_resistivity_and_conductivity

When I bought silver electrodes I got a pair, so I'm planning to use the other one as a cathode. Is there any reason for NOT using it as such?

Offline kephra

  • The older I get, the better I was
  • Administrator
  • Participant
  • *****
  • Posts: 7421
  • Likes: 51
  • Illegitimi Non Carborundum
    • The SilverTron Store Colloidal Silver Generators
Re: The choice of metal as cathode
« Reply #1 on: December 09, 2014, 07:46:52 AM »
There is no reason not to use copper, or not to use silver, or not to use stainless steel for the cathode.  The advantage is that's its a lot cheaper than silver.  If you have two silver rods, use them.  Then once your anode is used up, use the silver cathode for the anode, and use a piece of copper for the cathode if you want.
I never said you have to use copper for the cathode, just that you could, and the conductivity difference doesn't matter at all.
Colloidal Silver is only a bargain if you make it yourself.

Offline Gene

  • Expert
  • Participant
  • ***
  • Posts: 700
  • Likes: 3
Re: The choice of metal as cathode
« Reply #2 on: December 09, 2014, 12:31:15 PM »
Just to say it, the reason copper or stainless work for a cathode is because a colloidal silver making electrolysis cell is basically an electroplating cell where metal ions only come off the anode (more positive electrode in the cell) where if it were a true plating cell, those metallic ions would plate onto the cathode.  Its basically a one way deal.

Since no metal comes off the cathode, it can be a couple other acceptable metals as stated in a prior post, which as Kephra states, are much less expensive than silver and very easy to obtain (especially copper).  As he says, if you want to use a silver cathode, go right ahead though its no better nor any worse than a copper or stainless one.

In our use of this "plating cell", its really "broken" in the sense that the electrolyte we use prevents the metallic silver ions we're pulling into solution from plating out on the cathode where, instead, the concentration of those ions in solution grows to the point we want.