Thermodynamic and electrochemical study on the mechanism of formation of Ag(OH)4− in alkaline media

• Sensitive electrochemical techniques were used to evidence the formation of Ag(III).
• The required potential for the generation of Ag(III) was found by using UV–vis to monitor species being formed.
• A mechanism for the production of Ag(III) in the form of Ag(OH)4− is proposed.

A mechanism based on electrochemical, spectrophotometric and scanning electron microscopy (SEM) data in alkaline media is proposed for the generation of Ag(III) in the form of Ag(OH)4−. The formation of Ag(III) from Ag0 is a rather complex multistep process that involves several steps. The presence of soluble Ag(I) species as Ag(OH)2− is of paramount importance for the production of soluble Ag(OH)4−, whose decomposition time is shown to exceed 8 h.