Ionics

, Volume 16, Issue 2, pp 97–103 | Cite as

Enhanced long-term stability of bismuth oxide-based electrolytes for operation at 500 °C

  • Doh Won Jung
  • Juan C. Nino
  • Keith L. Duncan
  • Sean R. Bishop
  • Eric D. Wachsman
Original Paper

Abstract

Cubic-stabilized ((DyO1.5)x–(WO3)y–(BiO1.5)1 − x − y) electrolytes (DWSB) with much higher conductivity than (ErO1.5)0.2(BiO1.5)0.8, 20ESB, were developed through a double-doping strategy. (DyO1.5)0.08–(WO3)0.04–(BiO1.5)0.88, 8D4WSB, is the highest conductivity composition but underwent the greatest conductivity degradation at 500 °C due to its low total dopant concentration. The effect of dopant composition on conductivity behavior with time at 500 °C demonstrates that there is a trade-off between initial conductivity and long-term stability at this temperature. Therefore, it is necessary to find an optimal total and relative concentration of dopants to provide the enhanced long-term stability needed to make this DWSB electrolyte system feasible for 500 °C operation. To this end, it was found that (DyO1.5)0.25–(WO3)0.05–(BiO1.5)0.70, 25D5WSB, maintained a conductivity of 0.0068 S/cm without appreciable degradation after annealing at 500 °C for 500 h. Moreover, since bismuth oxide-based electrolytes do not exhibit any grain boundary impedance, the total conductivity of 25D5WSB is significantly higher than that of alternate electrolytes (e.g., GDC: Gd0.1Ce0.9O1.95) at this temperature.

Keywords

Bismuth oxide Electrolyte Conductivity Stability Electrochemical impedance spectroscopy 

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Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  • Doh Won Jung
    • 1
  • Juan C. Nino
    • 1
  • Keith L. Duncan
    • 1
  • Sean R. Bishop
    • 1
  • Eric D. Wachsman
    • 2
  1. 1.Department of Materials Science and EngineeringUniversity of FloridaGainesvilleUSA
  2. 2.University of Maryland Energy Research CenterUniversity of MarylandCollege ParkUSA

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