Chemical sensor based on silver/silver sulfide microelectrode

A simple method was used for the preparation of ion-selective 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 x 10(-6) to 1 x 10(-1) and from 1 x 10(-7) to x 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.