Effects of the additions of strontium gallate on Electrical conductivity of La0.9Sr0.1Ga0.8Mg0.2O3-δ

Abstract

Strontium and magnesium-doped lanthanum gallate La1-xSrxGa1-yMgyO3-δ (LSGM) is a promising solid electrolyte for using in solid oxide fuel cells, due to its high ionic conductivity at intermediate temperatures (600 – 800 ºC) compared to yttriastabilized zirconia (YSZ). In addition, LSGM has negligible electronic conductivity and high chemical stability over a broad range of oxygen partial pressures [1-3]. In this work, the composition La0.9Sr0.1Ga0.8Mg0.2O3-δ with small additions of strontium gallate was prepared by solid-state reaction and the influence of the additive on the ionic conductivity and phase composition was investigated. The sintered solid electrolytes achieved densities higher than 95% of the theoretical value and the average grain size amounts 2.40 μm after sintering at 1350°C. The contents of secondary phases decreased with increasing strontium gallate additions. The additive was found to have a beneficial effect on the bulk ionic conductivity.