Stability and mixed ionic electronic conduction in Gd-2(Ti1-xMox)(2)O-7 under anodic conditions

The electrical conductivity and the stability range of compositions in the Gd2Ti2O7-Gd2Mo2O7 pyrochlore solid solution have been investigated to determine their potential as anode materials in solid oxide fuel cells. While the total electrical conductivity increases with Mo content, the P-O2 stability range narrows to two orders of magnitude in P-O2 for y=0.7 in Gd-2(Ti1-yMoy)(2)O-7. The y=0.5 composition is a good compromise for the anode, exhibiting high levers of conductivity and an acceptable stability range of P-O2. Blocking electrode measurements on this composition show the conductivity to be primarily electronic but with an ionic conductivity which nevertheless reaches reasonably high values.