Electrochemical interaction between silver and sulfur in sodium sulfide solutions

Abstract

Corrosion of silver and gold in sulfur-containing environments has been an industrial problem. The current study is concerned with the corrosion reaction behavior of silver in sodium sulfide solutions. An electrochemical investigation of silver corrosion has been carried out using a potentiostat, and the resulting corrosion products have been identified with the help of scanning electron microscopy (SEM), X-ray diffraction (XRD), and Raman spectroscopy. The effect of a concentration of sodium sulfide, pH, temperature, and electrical potential on the corrosion behavior of silver was investigated using Tafel plots and potentiodynamic polarization. The corrosion products under the conditions studied were found to be mainly silver sulfide and occasionally silver oxide. The corrosion rate was found to be positively influenced by both the pH of the solution and the concentration of sodium sulfide.