Synthesis and properties of fuel cell anodes based on (La0.5+x Sr0.5-x )(1-y) Mn0.5Ti0.5O3-delta (x=0-0.25, y=0-0.03)

Abstract

Results are presented of studying electrochemical properties of perovskite-like solid solutions (La0.5 + x Sr0.5 - x )(1 - y) Mn0.5Ti0.5O3 - delta (x = 0-0.25, y = 0-0.03) synthesized using the citrate technique and studied as oxide anodic materials for solid oxide fuel cells (SOFC). X-ray diffraction (XRD) analysis is used to establish that the materials are stable in a wide range of oxygen chemical potential, stable in the presence of 5 ppm H2S in the range of intermediate temperatures, and also chemically compatible with the solid electrolyte of La0.8Sr0.2Ga0.8Mg0.15Co0.05O3 - delta (LSGMC). It is shown that transition to a reducing atmosphere results in a decrease in electron conductivity that produced a significant effect on the electrochemical activity of porous electrodes. Model cells of planar SOFC on a supporting solid-electrolyte membrane (LSGMC) with anodes based on (La0.6Sr0.4)(0.97)Mn0.5Ti0.5O3 - delta and (La0.75Sr0.25)(0.97)Mn0.5Ti0.5O3 - delta and a cathode of Sm0.5Sr0.5CoO3 - delta are manufactured and tested using the voltammetry technique.