Synthesis and Characterization of La10Si6O27 and Ce0.9Gd0.1O1.95 Solid Oxide Fuel Cell Electrolyte Material

Abstract

A Composite oxide ionic conductor consisting of La10Si6O27(LASIO) and Ce0.9Gd0.1O1.95(GDC) was synthesized by a modified sol-gel method. The La10Si6O27powders prepared by modified sol-gel synthesis were coated with GDC gel and latter calcined to form a La10Si6O27- Ce0.9Gd0.1O1.95composite material. The structural and microstructural properties of the composite were investigated using powder XRD, SEM and TMA. EIS was conducted in air on the sintered pellets to evaluate the electrochemical performance of the pellets. The conductivity of the composite electrolyte at 973 K was 26 mS /cm which is two orders of magnitudes higher than that for the pure LASIO but lower than that of the GDC (30 mS/cm). The thermal expansion of the composite electrolyte is similar to that obtained for the LASIO.