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 investigate d to determine their potential as anode materials in solid oxide fuel cells. While the total electrical conductivity increases with Mo conte nt, the P-O2 stability range narrows to two orders of magnitude in P-O 2 for y=0.7 in Gd-2(Ti1-yMoy)(2)O-7. The y=0.5 composition is a good c ompromise for the anode, exhibiting high levers of conductivity and an acceptable stability range of P-O2. Blocking electrode measurements o n this composition show the conductivity to be primarily electronic bu t with an ionic conductivity which nevertheless reaches reasonably hig h values.