Preparation and characterization of solid electrolytes for solid oxide fuel cells. Quarterly report, July 1--September 30, 1996

Technical Report · Tue Dec 31 04:00:00 EST 1996

DOI:https://doi.org/10.2172/584870· OSTI ID:584870

During this quarter, the authors have analyzed EXAFS spectra of rare earth doped ceria and identified Gd and Sm doped ceria electrolytes for further investigations in this project. Although electrical properties of the material have been examined in detail, very little work has considered the microstructural/property relationships, particularly in relationship to atomic and geometric structures of these ceria based oxides. The authors have observed an ionic conductivity of 8.3 {times} 10{sup {minus}2} S/Cm in the (CeO{sub 2}){sub 0.8}(GdO{sub 1.5}){sub 0.2} at 800 C which is approximately four times that of Y{sub 2}O{sub 3} doped ZrO{sub 3} doped ZrO{sub 2} at the same temperature. The fraction of Ce{sup +4} ions reduced to Ce{sup +3} as a function of temperature and oxygen partial pressure. The partial reduction of cerium oxide generates mobile electrons and causes electronic conductivity in the electrolyte at temperatures above 500 C. In this quarter, the authors have attempted to measure the microstructural properties using SEM, TEM and HVC STM techniques. Other parts of this investigation are also discussed.

• Research Organization: Southern Univ. and A and M Coll., Baton Rouge, LA (United States). Dept. of Physics
• Sponsoring Organization: USDOE Assistant Secretary for Fossil Energy, Washington, DC (United States)
• DOE Contract Number: FG22-95MT95016
• OSTI ID: 584870
• Report Number(s): DOE/MT/95016--T3; ON: DE98004022
• Country of Publication: United States
• Language: English

Related Subjects

30 DIRECT ENERGY CONVERSION
36 MATERIALS SCIENCE
BATTERY SEPARATORS
CERIUM OXIDES
GADOLINIUM
IONIC CONDUCTIVITY
MEMBRANES
MICROSTRUCTURE
PROGRESS REPORT
SAMARIUM
SOLID ELECTROLYTE FUEL CELLS
SOLID ELECTROLYTES