Partial electronic and oxide ion conductivity in La0.7Sr0.3Ga0.6Fe0.4O3 was investigated in this study by the ion blocking method. It was seen that La0.7Sr0.3Ga0.6Fe0.4O3 stably exhibited the electronic hole conduction over wide O partial pressure. The estimated oxide ion conductivity decreased with decreasing PO2 and this seem to be caused by decreasing amount of VO¨ which was balanced with Fe valence number. The estimated transport number of oxide ion was reasonably agreed with those estimated by O concentration cells. It was found that the theoretical O permeation rate in La0.7Sr0.3Ga0.6Fe0.4O3 was much larger than observed values. Therefore, it was expected that the O permeation rate could be improved by increasing activity of surface catalyst.

Estimation of Theoretical Oxygen Permeation Rate through La(Sr)Ga(Fe)O3 Mixed Conductor. T.Ishihara, S.Ishikawa, T.Furuno, C.Yu, M.Ando, H.Nishiguchi, Y.Takita: Solid State Ionics, 2004, 175[1-4], 367-70