Sur l'utilisation d'une electrode ponctuelle dans les cellules à oxyde electrolyte solide . I. Application aux mesures thermodynamiques et à la détermination du nombre de transport electronique de l'electrolyte</SBT>
Under low oxygen pressures, the oxygen exchange rate is very low between the triple contact of an electrode of the type: metal, O 2/solid oxide electrolyte and the surrounding gas. We confirmed that this low exchange rate may cause erroneous calculations of the electronic transport number of solid oxides when gaseous systems are involved in the measurement. Also, for this low exchange rate, local equilibrium often prevails at the triple contact. Under such conditions the electrode can be used for micropotentiometric measurements. We have perfected the technique using point electrodes. Its application to different particular reactions allows a significant improvement in thermodynamic and electronic transport measurements.