Partial electronic conductivity and electrolytic domain of La0.9Sr0.1Ga0.8Mg0.2O3−δ

The partial electronic conductivity of La0.9Sr0.1Ga0.8Mg0.2O3−δ has been measured as a function of temperature (T) and oxygen activity (aO2) in the ranges of 1073≤T/K≤1273 and 10−1.5≤aO2≤10−34.6, respectively, by using an ion-blocking, polarization technique. The p- and n-type conductivities may best be estimated asσp/S cm−1=(98±14)exp−1.12±0.12 eVkT(aO21/4),σn/S cm−1=(1.8±0.2)×108exp−4.14±0.10 eVkT(aO2−1/4). omparison with the literature, the p-type conductivity of LaGaO3-based oxides seems to increase as the amount of Sr with its activation energy little influenced. From the ionic and partial electronic conductivities, the electrolytic domain boundaries of La0.9Sr0.1Ga0.8Mg0.2O3−δ have been located: the lower boundary, e.g. at 1000°C is 10−23 atm of oxygen partial pressure.