We demonstrate the applicability of LAMOX as an electrolyte for solid oxide fuel cells (SOFC) by preparing two anode-supported cells based on La0.9Dy0.1Mo2O9 and La0.9Dy0.1Mo1W1O9, and operating at 625 degrees-700 degrees C under single chamber conditions. The two cells, supported by a composite of NiO and Gd-doped ceria (GDC), are initialized with a porous Ni+GDC disk to catalyze the partial oxidation reaction of methane. The partially oxidized methane reduces NiO to Ni catalyst and activates the cell at 650 degrees C. A typical membrane electrode assembly of the single chamber SOFC cell consists of a 60-mu m-thick La0.9Dy0.1Mo2O9 electrolyte, an anode of Ni+GDC, and a cathode of lanthanum strontium cobalt ferrite. Its peak power measures 220 mW/cm2 at 700 degrees C in a tubular chamber of 15 mm in diameter, with the total methane/air flow rate of 350 mL/min and CH4:O-2=2:1.