Syntheses of La_(1-x)Sr_xMnO_3 Nanopowders by Hydrothermal Method

摘要

Lanthanum strontium manganese, LSM, has been considered as one of the most prospect materials for solid oxide fuel cell (SOFC) applications due to its high electrode activity for the oxygen reduction reaction, high electronic conductivity and chemical as well as mechanical compatibility with the established solid electrolytes. In this work, Sr-doped LaMnO_3 was synthesized by hydrothermal method and the effect of Sr doping on lanthanum manganese (LSM) was investigated. The La_(1-x)Sr_xMnO_3 (0≤x≤0.4) nanopowders were prepared under different reaction conditions by hydrothermal syntheses. The synthesized nanopowders were characterized the crystalline by X-ray diffraction. The microstructure and particle size of the nanopowders were analyzed by FE-SEM and intercept method. The particles size of LSM powders was approximately ～170 nm when used KOH as a precipitant. The relative density of LSM was over 97% by Archimedes density method. The electrical conductivity of the sintered pellet was measured at 750°C in air by DC four point probe method, and the electrical conductivity was 21.3～63.85 S/cm. The physical and electrical properties of Sr-doped lanthanum manganese were discussed.