The Role of the Electrolyte in the Fabrication of Ag|AgCl Reference Electrodes for pH Measurement

Ag|AgCl reference electrodes have been prepared by anodising silver under constant potential in an aqueous electrolyte containing the chloride salt of three different alkali metals. These have been compared to Ag|AgCl reference electrodes anodised in hydrogen chloride that are conventionally used. Our research reveals that the size of the alkali metal cation has an influence on the Ag|AgCl electrode microstructure, with smaller cations resulting in a more porous material and improved electrode stability. This research has positive implications for improving the performance of Ag|AgCl reference electrodes for pH measurement.