The partial electron-hole conductivity of the bulk and the grain boundary of 1mol%

Sr-doped LaGaO3 was measured separately using a dc-polarization method

employing an oxygen ion-blocking cell. The electronic transference number for the

electron-hole at the grain boundary was found to be greater than that in the bulk.

This was because the oxygen vacancy depletes more severely in the grain boundary

area than the electron-hole does to form the space charge zone, due to its higher

effective charge compared to that of the electron-hole. Such a local variation in the

electronic transfer number thus confirmed that the conduction across the grain

boundary in 1mol% Sr-doped LaGaO3 was controlled by the space charge. These

results were consistent with those previously reported based on the ac impedance

studies.

The Enhanced Electronic Transference Number at the Grain Boundaries in Sr-

Doped LaGaO3. H.J.Park, S.Kim: Solid State Ionics, 2008, 179[27-32], 1329-32