The effect on performance of fabrication parameter variations of thick-film screen printed silver/silver chloride potentiometric reference electrodes

• A miniaturised, low cost solid state reference electrode is developed.
• Showing susceptibilities as low as +2 mV/decade of chloride concentration in various potassium chloride solutions.
• Their stability is also tested in a variety of pH buffer solutions resulting in susceptibilities in the range of +5 mV/pH.
• Satisfactory stability, therefore suitable for pH accuracies of ±0.1pH units over a modest chloride concentration range.

Thick-film screen printed silver–silver chloride (Ag/AgCl) reference electrodes have been fabricated and investigated as an alternative to liquid electrolyte Ag/AgCl reference electrodes. The performance of the electrodes was examined with variations of the potassium chloride (KCl) concentration in the final (top) layer of the electrode. Also, different types of binder (glass and polymer) were tested for the underlying Ag/AgCl layer. The addition of another layer on top of the KCl containing salt matrix layer has been found to provide a better stability in varying concentrations of KCl test solutions. The electrodes were found to give a satisfactory performance when tested for stability in different pH solutions.