Dielectric and direct-current measurements were carried out on La0.8Sr0.2GaO3–δ, which had a high potential for the electrolyte material in a solid oxide fuel cell, so as to elucidate the correlation between O2– diffusion and electric conduction. A dielectric relaxation showed up in loss tangent. The relative relation of activation energies as to dielectric relaxation and direct-current conduction suggested the ionic conduction due to O2– diffusion assisted by free single O vacancies taking place. The change of direct-current conductive behavior associated with attenuation of dielectric relaxation around 950K indicated that another type of O2– diffusion dominates the ionic conduction at high temperatures.

Ionic Conduction due to Oxygen Diffusion in La0.8Sr0.2GaO3–δ Electrolyte. E.Iguchi, S.Nakamura, F.Munakata, M.Kurumada, Y.Fujie: Journal of Applied Physics, 2003, 93[6], 3662-4