A FIELD-INDUCED POISING TECHNIQUE FOR PROMOTING CONVERGENCE OF STANDARD ELECTRODE POTENTIAL VALUES OF THERMALLY OXIDIZED IRIDIUM PH SENSORS

An electrochemical technique based on reversible charge ejection/injection is shown to be an effective procedure for bringing about the convergence of standard electrode potential values in a batch of thermally prepared iridium oxide pH sensors. Such a convergence simplifies electrode calibration procedures. The rationale for the technique and the results obtained are discussed in terms of adjustment of the proportions of iridium(III) and iridium(IV) oxides at the electrode surface.