title: Coprecipitation synthesis and characterization of La0.8Sr0.2Ga(0.8-x)Mg0.2Co(x)O2.8 for intermediate temperature solid oxide fuel cell electrolytes.
abstract: La0.8Sr0.2Ga(0.8-x)Mg0.2CO(x)O2.8 (LSGMC) electrolyte powders containing different amount of Co (0 < or = x < or = 0.15) were prepared by ammonium carbonate coprecipitation method. The precursors, the calcined powders, and the sintered pellets were characterized by thermogravimetry/differential thermal analysis, X-ray diffractometry, scanning electron microscopy, and an impedance analyzer. The thermal decomposition of the LSGMC precursors was completed at around 900 degrees C with the total weight loss of approximately 35%. The LSGMC samples sintered at 1350 degrees C consisted of the pure perovskite structure. The ionic conductivity was significantly improved by Co doping for the Ga-site of the La0.8Sr0.2Ga0.8Mg0.2O2.8 (LSGM) electrolytes. The ionic conductivity of LSGMC (x = 0.1) exhibited the highest values of 1.6 x 10(-1) S cm(-1) at 700 degrees C with an activation energy for the oxide-ion conduction of 0.29 eV. The results of this study indicated that the Co-doped LSGM electrolytes had excellent properties for use as an electrolyte in an IT-SOFC and the ammonium carbonate coprecipitation process could be employed as the efficient method for the preparation of the Co-doped LSGM electrolytes.
authors.affiliation: Department of Chemical Engineering, Kyungwon University, San 65 Bokjung-Dong, Seongnam, Gyeonggi-Do 461-701, Korea.
authors.forename: Jin Goo
authors.initials: JG
authors.lastname: Lee
authors.forename: Hyon Hee
authors.initials: HH
authors.lastname: Yoon
mesh_terms: D011232:Chemical Precipitation; D003460:Crystallization / Q000379:methods*; D011211:Electric Power Supplies; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007811:Lanthanum / Q000737:chemistry*; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D010087:Oxides / Q000737:chemistry; D010316:Particle Size; D013696:Temperature
chemical_list: D010087:Oxides; D007811:Lanthanum