Ionic Conductivity of Doped Lanthanum Gallate and Strontium Gallate Composites

Author(s)

Reis, S. L. ; Muccillo, E. N. S. ; Zhou, XD ; Mogensen, M ; Gur, TM ; Kawada, T ; Traversa, E ; Cai, Q

• Document type: Journal article
• Source: IONIC AND MIXED CONDUCTING CERAMICS 11 (IMCC 11); v. 80, n. 9, p. 9-pg., 2017-01-01.

Abstract

Polycrystalline ceramic solid electrolytes based on strontium- and magnesium-doped lanthanum gallate exhibit high ionic conductivity and find potential application in solid oxide fuel cells operating at intermediate temperatures. Sintering of this solid electrolyte is usually carried out at high temperatures, being responsible for loss of Ga and consequent formation of impurity phases. In this work, composites consisting of La0.9Sr0.1Ga0.8Mg0.2O3-delta with additions of strontium gallate were prepared by solid state reaction, and the influence of the additive on electrical conductivity and phase composition of the composite electrolyte was investigated. The sintered density of composites is higher than 95% of the theoretical value after sintering at 1350 degrees C. The contents of impurity phases decreased with increasing additions of strontium gallate. The overall ionic conductivity of the composites is higher than that of LSGM. This effect is attributed to the decrease in the fraction of free MgO at grain boundaries in the composites. (AU)

• FAPESP's process: 13/07296-2 - CDMF - Center for the Development of Functional Materials
• Grantee: Elson Longo da Silva
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC