Vacancies oxide ion

Where Vo", Oo, and e are the oxygen vacancy, oxide ion in a normal anion site in the YSZ lattice, and an electron in the metal (Ag). Thus, the half-cell reaction for the sensor becomes... 

Fig. 8.2 Comparison between different perovskite B-site ions comparing stability under fuel conditions and ability to reduce coordination number to allow vacancy oxide ion conductivity of transition metals in perovskite oxides...

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