ELECTROCHEMICAL BEHAVIOR OF ORDERED OXYGEN-DEFICIENT PEROVSKITES LnBaCo2O5+ (Ln = Pr, Nd, Sm and Gd) USED AS CATHODE OF IT-SOFC
LnBaCo2O5+δ (Ln=Pr, Nd, Sm and Gd) double perovskite oxides have been synthesized by a combined EDTA and citrate complexing method and characterized as cathode for intermediate temperature SOFC (IT-SOFC) by powder X-ray diffraction (XRD), electrical conductivity and thermal expansion coefficient(TEC) measurements, as well as the electrochemical impedance spectra measurement. According to the XRD results, a single phase structure has been formed for LnBaCo2O5+δ after calcinations at 1100℃ for 10h, and the lattice volume decreases from Ln=Pr to Gd. LnBaCo2O5+δ oxides show high electrical conductivity, large thermal expansion coefficient (TEC) and outstanding electrochemical performance. But the properties of LnBaCo2O5+δ oxides are greatly influenced by A-site Ln3+ ions. The electrical conductivity, TEC and electrocatalytic activity decrease on going from Ln=Pr to Gd. Compared with other oxides, PrBaCo2O5+δ exhibits better electrochemical performance (lower polarization resistance), which should be largely contributed to its higher oxygen ion conductivity, superior oxygen diffusion rates and faster surface exchange kinetics.
CHENGJUN ZHU CUISHAN YI TIEZHU DING WENPING ZHOU LUOMENG CHAO
Key Laboratory of Semiconductor Photovoltaic Technology at Universities of Inner Mongolia Autonomous Key Laboratory of Semiconductor Photovoltaic Technology at Universities of Inner Mongolia Autonomous
国际会议
The 12th Asian Conference on Solid State Ionics(第十二届亚洲固态离子学会议暨第十五届中国固态离子学会议)
武汉
英文
709-717
2010-05-02（万方平台首次上网日期，不代表论文的发表时间）