Abstract
The cyanide-free silver plating bath that we developed produced good silver film, but the cell voltage of the bath increased over time if electrodeposition was conducted continuously. Green film also formed on the silver anode with increasing voltage. To clarify these phenomena, we studied the anodic polarization behavior of the silver electrode in the cyanide-free bath.
The X-ray diffraction pattern for the green film agreed with that of AgI. Anodic polarization curves for the silver electrode indicated that less-conductive film formed on the electrode when the potential exceeded-0.3V. The polarization curve limiting current was increased by agitating the bath or increasing KI concentration. These results iudicate that Ag was dissolved into the solution via AgI rather than dissolving directly into the bath.
