A Liquid-phase Ion Gun Technique for Generating Sulfide Ions on Metal Surfaces

Abstract

A new liquid-phase ion gun （LPIG） technique was developed for safe generation of sulfide ions on metal surfaces in solution, though the LPIG was originally a local chloride ion-generating system used to investigate localized corrosion on metal surfaces as an application of scanning electrochemical microscopy. A silver/silver sulfide microelectrode was used as a liquid-phase sulfide ion gun （LPSIG） instead of a silver/silver chloride microelectrode of an LPIG. Cathodic polarization of the LPSIG microelectrode resulted in the generation of hydrogen sulfide ions in the vicinity of the microelectrode and provided a safe electrochemical environment containing hydrogen sulfide ions. The generation of hydrogen sulfide ions from the LPSIG and the degradation behavior of surfaces of a silver or a type-316L stainless steel are mainly reviewed here. The potential of the LPSIG technique for investigation of hydrogen sulfide-induced corrosion is also discussed.