A novel family of Nb-doped Bi0.5Sr0.5FeO3-delta perovskite as "cathode material for intermediate-temperature solid oxide fuel cells

作者：Gao, Lei; Li, Qiang^*; Sun, Liping; Zhang, Xianfa; Huo, Lihua; Zhao, Hui^*; Grenier, Jean-Claude

来源：Journal of Power Sources, 2017, 371: 86-95.

DOI：10.1016/j.jpowsour.2017.10.036

• Solid oxide fuel cells
• Cobalt-free cathode material
• Electrochemical performance
• Oxygen reduction kinetics

Cobalt-free provskite oxides Bi0.5Sr0.5Fe1-xNbxO3-delta (BSFNx, x = 0.05, 0.10 and 0.15) were prepared and evaluated as cathode materials for intermediate temperature solid oxide fuel cells (IT-SOFCs). In particular, the effects of Nb substitution on phase evolution, thermal expansion behavior and electrochemical performance were systematically investigated. The average thermal expansion coefficient (TEC) of BSFNx decreases from 13.3 x 10(-6) K-1 at x = 0.05 to 12.6 X 10(-6) K-1 at x = 0.15 within a temperature range of 50800 degrees C. Among the BSFNx materials, Bi0.5Sr0.5Fe0.9Nb0.1O3-delta (BSFN0.10) oxide shows the best electrochemical performance. The polarization resistances (R-p) of BSFN0.10 cathode on CGO electrolyte are 0.038, 0.075 and 0.156 Omega cm(2) at 700, 650 and 600 degrees C, respectively. Meanwhile the maximum power densities of the anode-supported single cells are 1.28, 1.54 and 1.34 W cm(-2) at 700 degrees C for BSFNx cathodes with x = 0.05, 0.10, and 0.15, respectively. Furthermore, the relationship study of oxygen partial pressure dependence on R-p indicates that the oxygen reduction reaction (ORR) rate-limiting step is the oxygen adsorption-dissociation on the electrode surface. The desirable electrochemical performance demonstrates that BSFNx oxides are potential cathode materials for IT-SOFCs.

• 出版日期2017-12-15
• 单位黑龙江大学