Preparation and characterization of La1.75Y0.25Mo2-xAlxO9-δ as solid electrolyte for intermediate temperatures SOFC

Yttrium and aluminium co-substitutions on lanthanum molybdate ceramics with the nominal formula La1.75Y0.25Mo2-xAlxO9-?? (LYMA, x = 0, 0.1, 0.2, 0.3 0.4) were synthesized by citric acid-nitrate combustion method used for preparation of solid electrolyte intermediate-temperature oxide fuel cells (ITSOFCs). Phase composition, structure, conductivity electrical properties LYMA have been investigated as a function content X-ray diffraction, scanning electron microscopy electrochemical impedance spectroscopy, respectively. Experimental results showed that substitution La Mo appropriate amounts Y Al can effectively stabilize ?-form La2Mo2O9 at room temperature inhibit its phase transition to ?-form. The exhibited better sinterability where relative density samples sintered 950?C 4 h was higher than 95%TD. performance found be related Al-content. La1.75Y0.25Mo1.8Al0.2O8.7 high ion (?= 42mS/cm 800?C) low activation energy (Ea 1.18 eV). These preliminary indicate is promising IT-SOFCs.