CHEMICAL SENSOR BASED ON SILVER/SILVER SULFIDE MICROELECTRODE

A simple method was used for the preparation of ionselective electrodes for silver and sulfide ions with micrometric and small dimensions. The electrode was fabricated by etching a silver wire to a fine point and then coating with an electrophoretically deposited paint, which is subsequently heat-cured to isulate all but the very end of the tip. The constructed electrode exhibits a potentiometric response to silver and sulfide ions with Nernstian slopes. The sensor has a linear response in the concentration ranges from 1 × 10-6 to 1 × 10-1 and from 1 × 10-7 to × 10-1 M for silver and sulfide ions, respectively. The microelectrode could be used as the indicator electrode for measuring both Ag| and S2 by analytical titration. The introduced microelectrode is simple and has long-term stability.