Miniaturized reference electrode with a negative feedback function for potential stabilization

A thin-film Ag/AgCl reference electrode with a negative feedback function to stabilize the potential is proposed. A three-electrode system consisting of three Ag/AgCl electrodes was used and was controlled by a potentiostat. The electrode to provide the standard potential was used as the reference electrode, which was surrounded by a Ag/AgCl auxiliary electrode. When the reference electrode potential changed in response to changes in the concentration of Cl^- ions, large current flowed on the auxiliary electrode and the concentration of Cl^- ions and the reference electrode potential recovered to the initial values. The reference electrode potential changed significantly when a solution of a different Cl^- concentration was flowed and the feedback function was not working. However, the feedback function suppressed the changes remarkably.