A stable La sub(1.95)Ca sub(0.05)Ce sub(2)O sub(7- delta ) as the electrolyte for intermediate-temperature solid oxide fuel cells

The La sub(1.95)Ca sub(0.05)Ce sub(2)O sub(7- delta ) (LCCO) material is successfully synthesized using the Pechini method. The synthesized powders are exposed to atmospheric CO sub(2) and H sub(2) with 3% H sub(2)O at 700 degree C. The treated LCCO powders are investigated using X-ray diffraction (XRD) to study the chemical stability. According to the XRD results, LCCO is very stable and shows no reactions with CO sub(2) or H sub(2)O. A fuel cell with the LCCO electrolyte is prepared using the suspension spray method and is tested in the range from 600 degree C to 700 degree C using humidified hydrogen (3% H sub(2)O) as the fuel and static air as the oxidant. An open-circuit potential of 0.832 V and a maximum power density of 259 mW cm super(-2) are obtained for a single cell with an interface resistance of 0.23 Omega cm super(2) at 700 degree C.