Electrical Properties of Novel La0. 2Sr0.7-xCaxTi0.95Fe0.05O3-δ Based Fuel Electrode for Solid Oxide Cell

Abstract

A novel La0. 2Sr0.7-xCaxTi0.95Fe0.05O3-δ (LSCFT-x) fuel electrode compositions for high-temperature solid oxide fuel cell application are synthesized using glycine-nitrate synthesis method. To understand the influence of Sr/Ca ratio on electrical conductivities of different compositions of LSCFT, the DC four-probe conductivity measurements of porous electrode layers has been performed. Conductivities have been measured at three different atmospheres: air, 1% H2 + 3% H2O + 96% Ar, and 97% H2 + 3% H2O. The crystal structure and microstructure have been studied using X-ray diffraction and SEM, respectively to confirm the phase purity and visualize the microstructure of studied electrode layers. It has been shown that the LSCTF material behave like semiconductor and the conductivity is significantly dependent of Ca concentration in A-site. The maximal total electrical conductivity of porous electrode layer made of LSCFT was 5.5 S cm− 1 at 850°C characteristic for the LSCFT-45 material in 97% H2 + 3% H2O atmosphere.