The competitive ionic conductivities in functional composite electrolytes based on the series of M-NLCO (M = Ce sub(0.8Sm) sub(0).2O sub(2-[delta], Ce) sub(0).8Gd sub(0.2O) sub(2)-[delta], Ce sub(0.8Y) sub(0).2O sub(2-[delta]; NLCO = 0.53Li) sub(2)CO sub(3-0.47Na) sub(2)CO sub(3))

• Published in: International journal of hydrogen energy 2011-05, Vol.36 (11), p.6840-6850
• Main Authors: Xia, Yanjie, Bai, Yijia, Wu, Xiaojie, Zhou, Defeng, Liu, Xiaojuan, Meng, Jian
• Format: Article
• Language: English
• Subjects: Conductivity; Dopants; Electrolytes; Grain boundaries; Ionic conductivity; Microstructure; Sintering
• ISSN: 0360-3199
• DOI: 10.1016/j.ijhydene.2011.02.118

In order to identify competitive ion-conducting materials in ceria-carbonates composite electrolytes, M-NLCO (M = Ce sub(0.8Sm) sub(0).2O sub(2-[delta] (SDC), Ce) sub(0).8Gd sub(0.2O) sub(2)-[delta] (GDC), Ce sub(0.8Y) sub(0).2O sub(2-[delta] (YDC); NLCO = 0.53Li) sub(2)CO sub(3-0.47Na) sub(2)CO sub(3) sintered at different temperatures (600[deg] C, 625[deg] C, 650[deg] C, 675[deg] C and 700[deg] C) have been prepared and characterized. It is found that independent of systems, the 675[deg] C-sintered composites in M-NLCO always present the highest conductivities because of the best NLCO distribution and interfacial microstructures. Moreover, among three composites (sintered at 675[deg] C), the total ([sigma]) sub(t)) and grain boundary ([sigma] sub(gb) conductivities measured at 600[deg] C are ranked as: SDC-NLCO (, [inline image]) > GDC-NLCO (, [inline image]) > YDC-NLCO (, [inline image]), which is attributed to ionic-radius compatibility between the dopant and the host as well as the NLCO distribution and interfacial microstructures. It can be concluded that ionic-radius compatibility between the dopant and the host, NLCO distribution and interfacial microstructures have important effects on improving ionic conductivities for ceria-carbonates composite electrolytes.)