Preparation and electrochemical performance of Pr2Ni0.6Cu0.4O4 cathode materials for intermediate-temperature solid oxide fuel cells

Cathode material Pr2Ni0.6Cu0.4O4 (PNCO) for intermediate-temperature solid oxide fuel cells (IT-SOFCs) is synthesized by a glycine-nitrate process using Pr6O11, NiO, and CuO powders as raw materials. X-ray diffraction analysis reveals that nanosized Pr2Ni0.6Cu0.4O4 powders with K2NiF4-type structure can be obtained from calcining the precursors at 1000 degrees C for 3 h. Scanning electron microscopy shows that the sintered PNCO samples have porous microstructure with a porosity of more than 30% and grain size smaller than 2 mu m. A maximum conductivity of 130 S cm(-1) is obtained from the PNCO samples sintered at 1050 degrees C. A single fuel cell based on the PNCO cathode with 30 mu m Sm0.2Ce0.8O1.9 (SCO) electrolyte film and a 1 mm NiO-SCO anode support is constructed. The ohmic resistance of the single Ni-SCO/SCO/PNCO cell is 0.08 Omega cm(2) and the area specific resistance (ASR) value is 0.19 Omega cm(2) at 800 degrees C. Cell performance was also tested using humidified hydrogen (3% H2O) as fuel and air as oxidant. The single cell shows an open circuit voltage of 0.82 V and 0.75 V at 700 degrees C and 800 degrees C, respectively. Maximum power density is 238 mW cm(-2) and 308 mW cm(-2) at 700 degrees C and 800 degrees C, respectively. The preliminary tests have shown that Pr2Ni1-xCuxO4 materials can be a good candidate for cathode materials of IT-SOFCs. (C) 2010 Elsevier B.V. All rights reserved.