Enhancement on densification and crystallization of conducting La0.7Sr0.3VO3 perovskite anode derived from hydrothermal process

Abstract

La1-xSr x VO3 (LSV)-based perovskite anodes are chemically and electrochemically stable under SOFC operating conditions. The main objective of this study was to investigate the feasibility of obtaining La0.7Sr0.3VO3 nanopowder from a novel hydrothermal method at relative low-temperature (∼200 °C). The particle size of hydrothermally-processed La0.7Sr0.3VO3 powder was as fine as 50 nm based on transmission electron microscopy observation. As a result, the better crystallization and densification was demonstrated from La0.7Sr0.3VO3 nanopowders synthesized via a hydrothermal route in comparison with a solid-state reaction (SSR) method. La0.7Sr0.3VO3 nanopowder shows a perovskite-type structure after heat-treated at 800 °C for 5 h in a reducing atmosphere (20% H2, 80% Ar). The hydrothermally treated La0.7Sr0.3VO3 showed high density of 96% that is better than the SSR process (86%). La0.7Sr0.3VO3 synthesized by the hydrothermal process shows metallic conducting behavior. Its conductivity reached 193 s cm-1 at 800 °C which is adequate for SOFC application.