Oxygen Ion Conductivity in the Electrolyte

2 Structure and Chemical Bonding at the Atomic Scale 2.1 Oxygen Ion Conductivity in the Electrolyte 

In case of low valence element substitution to either Ce02 or Zr02, the oxygen vacancy concentration, [Vq ], is primarily determined by the acceptor concentration, then the neutrality condition is  

The total conductivity, iTt, is the sum of ionic conductivity (ffj) and electronic conductivity (Ce)  

If the acceptor concentration is much larger than electron density, then oxygen vacancy concentration is constant as shown in (13). The electronic conductivity 

It is known that acceptor-doped Ce02 (e.g., Gd doped Ce02 - GDC) can be reduced at a very low oxygen partial pressure. Table 1 is a list of P 02 (atm) for various dopant levels, y, in Cei yGd Oi y2 at different temperatures. P 02 

---