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Silver plating on carbon for Ag4[Fe(CN)6] dep

Briefly I am attempting to plate nano carbon electrodes with silver that can later be oxidized to silver +1 in the presence of ferrocyanide to form an insoluble precipitate of Ag4[Fe(CN)6] for later use in electrochemical sensors. Unfortunately the only silver sources that I currently have are silver nitrate and silver wire. Based on an earlier thread I gather that silver nitrate cannot be electroplated without cyanide which due to safety regulations were I work is not feasible. Therefore I am wondering if it would be feasible to place a silver wire above the carbon electrode and oxidize the silver wire to form Ag+ and the subsequently reduce the Ag+ to Ag on the carbon. My concern is that oxidizing the silver wire may form some type of silver oxide that is not readily reduced or is insoluble. If you have any suggestions I would appreciate it.

Stephen W. Jones

2006

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2006

Hi Stephen. The way to do silver electroplating is from cyanide based silver electroplating solutions, a simple proven process for 100 years now. More than 95 percent of all silver plating is still done from cyanide solutions, and with the present state of the art I would not encourage anyone to move away from this technology. But if your facility absolutely forbids cyanide solutions, you might try the cyanide-free plating silver plating processes of the site's supporting advertiser EPI / Electrochemical Products Inc. [a finishing.com supporting advertiser].

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

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2006

Ferrocyanide based electrolyte (1% of potassium cyanide toxicity): 20 gm silver chloride(you can convert nitrate to chloride,add sodium chloride solution to nitrate solution)
40 gm potassium carbonate
40 gm potassium ferrocyanide [affil links]
1 lit water
optionally you can add 8o gm sodium sulphite
stainless steel anodes

pyrophosphate based electrolyte:
25 gm silver pyrophosphate(or nitrate or chloride)
25 gm ammonium carbonate
100 gm potassium pyrophosphate
1 lit water,stainless steel anodes
Hope to help and good luck!

Goran Budija